David Broockman
@dbroockman.bsky.social
Day job = Associate Prof. of Political Science at UC Berkeley. Tweets = personal views.
Some caveats: This is observational data from 27 districts in 2024. Voters might care about other things like compromise or ideology that we didn't study. For issue voting, projection is a threat to causal inference–but we discuss why that’s unlikely to explain our findings.
May 27, 2025 at 2:07 PM
Some caveats: This is observational data from 27 districts in 2024. Voters might care about other things like compromise or ideology that we didn't study. For issue voting, projection is a threat to causal inference–but we discuss why that’s unlikely to explain our findings.
Parties face a dilemma. Nominating moderates in close districts helps win—but most voters infer that candidates hold the party’s typical positions. To win some seats, a party needs a *nationwide* moderate reputation. But groups & others might not want to build it (e.g., by moderates in safe seats).
May 27, 2025 at 2:07 PM
Parties face a dilemma. Nominating moderates in close districts helps win—but most voters infer that candidates hold the party’s typical positions. To win some seats, a party needs a *nationwide* moderate reputation. But groups & others might not want to build it (e.g., by moderates in safe seats).
FINDING #3: Evidence that groups contribute to polarization. Group endorsements have major influence. Voters who learn about them are ~15 pp more likely to vote for endorsed candidates. This effect is driven by endorsements from liked groups—negative cues barely register.
May 27, 2025 at 2:07 PM
FINDING #3: Evidence that groups contribute to polarization. Group endorsements have major influence. Voters who learn about them are ~15 pp more likely to vote for endorsed candidates. This effect is driven by endorsements from liked groups—negative cues barely register.
This creates a problem for primary voters: party cues are useless in primaries where everyone's the same party. So primary voters stay confused about who's closest to them, even as they learn what candidates of their party stand for.
May 27, 2025 at 2:07 PM
This creates a problem for primary voters: party cues are useless in primaries where everyone's the same party. So primary voters stay confused about who's closest to them, even as they learn what candidates of their party stand for.
We found evidence that voters learn about candidates partly by learning national party reputations: a) voters somehow learn just as much about no-name candidates, & b) voters are 3x more likely to learn "stereotypical" positions (like Dems supporting healthcare) than unusual ones
May 27, 2025 at 2:07 PM
We found evidence that voters learn about candidates partly by learning national party reputations: a) voters somehow learn just as much about no-name candidates, & b) voters are 3x more likely to learn "stereotypical" positions (like Dems supporting healthcare) than unusual ones
When primary AND general voters learn a candidate agrees with them on an issue, they're ~14 percentage points more likely to vote for that candidate.
In generals, this includes when the closest candidate is an outpartisan–party loyalty isn’t everything.
In generals, this includes when the closest candidate is an outpartisan–party loyalty isn’t everything.
May 27, 2025 at 2:07 PM
When primary AND general voters learn a candidate agrees with them on an issue, they're ~14 percentage points more likely to vote for that candidate.
In generals, this includes when the closest candidate is an outpartisan–party loyalty isn’t everything.
In generals, this includes when the closest candidate is an outpartisan–party loyalty isn’t everything.
FINDING #1: General election voters know MORE about candidate positions than primary voters.
By election day, general election voters correctly identify 40% of candidate positions vs just 22% for primary voters.
By election day, general election voters correctly identify 40% of candidate positions vs just 22% for primary voters.
May 27, 2025 at 2:07 PM
FINDING #1: General election voters know MORE about candidate positions than primary voters.
By election day, general election voters correctly identify 40% of candidate positions vs just 22% for primary voters.
By election day, general election voters correctly identify 40% of candidate positions vs just 22% for primary voters.
This gives us a ton of unique data.
We measure knowledge & learning of 122 candidate issue positions in the 2024 Congressional primaries and 269 candidate issue positions in the 2024 Congressional generals.
We measure knowledge & learning of 122 candidate issue positions in the 2024 Congressional primaries and 269 candidate issue positions in the 2024 Congressional generals.
May 27, 2025 at 2:07 PM
This gives us a ton of unique data.
We measure knowledge & learning of 122 candidate issue positions in the 2024 Congressional primaries and 269 candidate issue positions in the 2024 Congressional generals.
We measure knowledge & learning of 122 candidate issue positions in the 2024 Congressional primaries and 269 candidate issue positions in the 2024 Congressional generals.
Conventional wisdom blames:
• Primary voters who closely follow politics & prefer extremists
• General election voters who are too ignorant of candidate positions—or too “intoxicated” by party loyalty—to vote for moderates over extremists
But our data tells a different story…
• Primary voters who closely follow politics & prefer extremists
• General election voters who are too ignorant of candidate positions—or too “intoxicated” by party loyalty—to vote for moderates over extremists
But our data tells a different story…
May 27, 2025 at 2:07 PM
Conventional wisdom blames:
• Primary voters who closely follow politics & prefer extremists
• General election voters who are too ignorant of candidate positions—or too “intoxicated” by party loyalty—to vote for moderates over extremists
But our data tells a different story…
• Primary voters who closely follow politics & prefer extremists
• General election voters who are too ignorant of candidate positions—or too “intoxicated” by party loyalty—to vote for moderates over extremists
But our data tells a different story…
🚨NEW PAPER: Why are Members of Congress so extreme?
We conducted a 4-wave panel of thousands of voters in 27 districts during last year’s primary AND general elections to trace polarization’s roots
The results challenge conventional wisdom… and suggest lessons for parties🧵👇
We conducted a 4-wave panel of thousands of voters in 27 districts during last year’s primary AND general elections to trace polarization’s roots
The results challenge conventional wisdom… and suggest lessons for parties🧵👇
May 27, 2025 at 2:07 PM
🚨NEW PAPER: Why are Members of Congress so extreme?
We conducted a 4-wave panel of thousands of voters in 27 districts during last year’s primary AND general elections to trace polarization’s roots
The results challenge conventional wisdom… and suggest lessons for parties🧵👇
We conducted a 4-wave panel of thousands of voters in 27 districts during last year’s primary AND general elections to trace polarization’s roots
The results challenge conventional wisdom… and suggest lessons for parties🧵👇
4. Consistent with that, we find some effects on attitudes towards work: people who get the transfer seem to value work *more*. There's a few potential explanations, including that people answering our survey sought to distance themselves from perception they would misuse the $.
December 2, 2024 at 7:00 PM
4. Consistent with that, we find some effects on attitudes towards work: people who get the transfer seem to value work *more*. There's a few potential explanations, including that people answering our survey sought to distance themselves from perception they would misuse the $.
3. Does getting a big cash transfer make ppl more supportive of... cash transfers? Liberal policy in general?
Surprising answer: no!
Political dispositions are hard to change! E.g., in interviews, some who received the transfer said they thought *others* would misuse it.
Surprising answer: no!
Political dispositions are hard to change! E.g., in interviews, some who received the transfer said they thought *others* would misuse it.
December 2, 2024 at 7:00 PM
3. Does getting a big cash transfer make ppl more supportive of... cash transfers? Liberal policy in general?
Surprising answer: no!
Political dispositions are hard to change! E.g., in interviews, some who received the transfer said they thought *others* would misuse it.
Surprising answer: no!
Political dispositions are hard to change! E.g., in interviews, some who received the transfer said they thought *others* would misuse it.
2. We find evidence consistent with "mood misattribution": recipients feel (a bit) warmer towards other racial groups, their own racial groups, & even governor of their state (& maybe both political parties).
But no fx on dispositions like authoritarianism or trust in democracy.
But no fx on dispositions like authoritarianism or trust in democracy.
December 2, 2024 at 7:00 PM
2. We find evidence consistent with "mood misattribution": recipients feel (a bit) warmer towards other racial groups, their own racial groups, & even governor of their state (& maybe both political parties).
But no fx on dispositions like authoritarianism or trust in democracy.
But no fx on dispositions like authoritarianism or trust in democracy.
Those null findings contrast with studies finding gov't-sponsored transfers mobilize, consistent with interpretations that it matters where people think $ is coming from when they experience income shocks. Our participants were (correctly) aware that this $ was not from gov't.
December 2, 2024 at 7:00 PM
Those null findings contrast with studies finding gov't-sponsored transfers mobilize, consistent with interpretations that it matters where people think $ is coming from when they experience income shocks. Our participants were (correctly) aware that this $ was not from gov't.
1. Resource theories of political participation would expect big increases in turnout & participation: participants had more $ and free time.
But we find nulls on participation, knowledge, etc. & can rule out observational association.
But we find nulls on participation, knowledge, etc. & can rule out observational association.
December 2, 2024 at 7:00 PM
1. Resource theories of political participation would expect big increases in turnout & participation: participants had more $ and free time.
But we find nulls on participation, knowledge, etc. & can rule out observational association.
But we find nulls on participation, knowledge, etc. & can rule out observational association.
🚨 NEW PAPER: When low-income Americans get $1,000/month for 3 years, what happens to their political views & behavior?
The OpenResearch Unconditional income Study reveals surprising findings about the effects of income on politics... 🧵
The OpenResearch Unconditional income Study reveals surprising findings about the effects of income on politics... 🧵
December 2, 2024 at 7:00 PM
🚨 NEW PAPER: When low-income Americans get $1,000/month for 3 years, what happens to their political views & behavior?
The OpenResearch Unconditional income Study reveals surprising findings about the effects of income on politics... 🧵
The OpenResearch Unconditional income Study reveals surprising findings about the effects of income on politics... 🧵
How did Fox News persuade? I think the most interesting result is that Fox News viewers agreed with our view of one mechanism: partisan TV filters out coverage bad for its side, leaving viewers in an echo chamber of facts that are only good for its side.
November 20, 2024 at 6:09 PM
How did Fox News persuade? I think the most interesting result is that Fox News viewers agreed with our view of one mechanism: partisan TV filters out coverage bad for its side, leaving viewers in an echo chamber of facts that are only good for its side.
This led to meaningful changes in areas that each network covered extensively, including views on the BLM protests and views towards Trump.
Although, contrary to maximalist accounts, didn't change views that the networks didn't cover extensively.
Although, contrary to maximalist accounts, didn't change views that the networks didn't cover extensively.
November 20, 2024 at 6:09 PM
This led to meaningful changes in areas that each network covered extensively, including views on the BLM protests and views towards Trump.
Although, contrary to maximalist accounts, didn't change views that the networks didn't cover extensively.
Although, contrary to maximalist accounts, didn't change views that the networks didn't cover extensively.
We found that watching CNN instead of Fox meaningfully changed many viewers' beliefs -- they were willing to learn facts unflattering to their side on CNN (and didn't learn the things Fox would have told them during that time).
November 20, 2024 at 6:09 PM
We found that watching CNN instead of Fox meaningfully changed many viewers' beliefs -- they were willing to learn facts unflattering to their side on CNN (and didn't learn the things Fox would have told them during that time).
Our experiment was conducted in late summer 2020, when CNN and Fox covered very different things....
November 20, 2024 at 6:09 PM
Our experiment was conducted in late summer 2020, when CNN and Fox covered very different things....
In our experiment, we recruited extremely conservative Fox News viewers to watch CNN instead for a month.
This is the exact audience existing research argues isn't persuaded by partisan TV because it simply cannot be persuaded.
But we find it can...
This is the exact audience existing research argues isn't persuaded by partisan TV because it simply cannot be persuaded.
But we find it can...
November 20, 2024 at 6:09 PM
In our experiment, we recruited extremely conservative Fox News viewers to watch CNN instead for a month.
This is the exact audience existing research argues isn't persuaded by partisan TV because it simply cannot be persuaded.
But we find it can...
This is the exact audience existing research argues isn't persuaded by partisan TV because it simply cannot be persuaded.
But we find it can...
3. Last, do partisan TV viewers get competing messages? Eg, do Fox viewers also watch lots of MSNBC, balancing it out? Largely no -- people almost always stick to one network.
These findings suggest partisan TV viewers could be persuaded.
These findings suggest partisan TV viewers could be persuaded.
November 20, 2024 at 6:09 PM
3. Last, do partisan TV viewers get competing messages? Eg, do Fox viewers also watch lots of MSNBC, balancing it out? Largely no -- people almost always stick to one network.
These findings suggest partisan TV viewers could be persuaded.
These findings suggest partisan TV viewers could be persuaded.
We find clear evidence of "selective exposure" -- people gravitate towards media that agrees with them.
BUT, partisan TV's audience isn't all extreme--weak partisans & Independents watch it, and their opinions aren't hugely different. There's room for them to be persuaded.
BUT, partisan TV's audience isn't all extreme--weak partisans & Independents watch it, and their opinions aren't hugely different. There's room for them to be persuaded.
November 20, 2024 at 6:09 PM
We find clear evidence of "selective exposure" -- people gravitate towards media that agrees with them.
BUT, partisan TV's audience isn't all extreme--weak partisans & Independents watch it, and their opinions aren't hugely different. There's room for them to be persuaded.
BUT, partisan TV's audience isn't all extreme--weak partisans & Independents watch it, and their opinions aren't hugely different. There's room for them to be persuaded.
We rely on a few unique data sources: Nielsen data tied to the voter file, smart TV data, cable box data, and TV diaries. They all point towards the same conclusions:
1. Partisan media's audience is sizable. No, most people don't want a lot of partisan TV -- but many do!
1. Partisan media's audience is sizable. No, most people don't want a lot of partisan TV -- but many do!
November 20, 2024 at 6:09 PM
We rely on a few unique data sources: Nielsen data tied to the voter file, smart TV data, cable box data, and TV diaries. They all point towards the same conclusions:
1. Partisan media's audience is sizable. No, most people don't want a lot of partisan TV -- but many do!
1. Partisan media's audience is sizable. No, most people don't want a lot of partisan TV -- but many do!
With Fox News hosts nominated for the cabinet, I wanted to share takeaways from two recently-accepted papers w @jkalla.bsky.social on partisan TV.
There's been much skepticism that partisan TV actually affects public opinion.
Our findings rebut that skepticism: partisan media matters! 🧵
There's been much skepticism that partisan TV actually affects public opinion.
Our findings rebut that skepticism: partisan media matters! 🧵
November 20, 2024 at 6:09 PM
With Fox News hosts nominated for the cabinet, I wanted to share takeaways from two recently-accepted papers w @jkalla.bsky.social on partisan TV.
There's been much skepticism that partisan TV actually affects public opinion.
Our findings rebut that skepticism: partisan media matters! 🧵
There's been much skepticism that partisan TV actually affects public opinion.
Our findings rebut that skepticism: partisan media matters! 🧵