Partisan Echo Chambers

Democrats love Vox, Republicans love Fox

New data show the media diet of members of Congress

Lindsey Cormack
Published in
5 min readDec 30, 2020


We’ve all heard that our media diet lives in an echo chamber, or that we only ever interact with stories that match our pre-existing dispositions to the world. Some people blame this one media outlets, other on individual sorting, and some see it as a predictable end to our fractured and specialized media/entertainment world. But what about politicians themselves, how to they contribute to this confirmatory news landscape?

Legislators spend a decent amount of their time trying to convince constituents that they are good at their jobs and well respected within the government. One way that legislators signal their abilities is by pushing constituents to content produced by differing media outlets. They will send reminders to constituents asking them to tune in to upcoming cable news broadcasts, alert them to positive coverage on media websites, and reproduce stories about them published in national newspapers.

From Rep James Comer’s July 24, 2020 e-newsletter “Fighting for Accountable, Reform-Minded Government”

But as we all know, this media environment is partisan. As PEW reports, democrats and republicans in the public use and trust different sources.

PEW results on media trust in the electorate

It comes as no surprise that FOX leads for conservatives, and over the past 10–15 years CNN has moved from a source considered in the middle, to one more preferred by the left. Democrats tend to trust a wider variety of sources, while Republicans have an overwhelming trust gap between FOX news and other outlets.

Looking at these major networks and cable producers, which are most advertised in congressional communications? Turning to the DCinbox database I checked to see who pushes what news sources and how this changes over time.

Over the past ten years, the most advertised outlets in official e-newsletters are FOX, CNN, NPR, and MSNBC. FOX is the clear leader, mostly due to GOP communications. While legislators do push to other forms of TV media, their total counts over the past decade are fall smaller, and do not exhibit any sort special attention in certain year, rather mentions are few and mostly flat across all years.

TV media advertised in official congressional e-newsletters 2010–2020

In order to visualize which legislators highlight different media in official e-newsletters and how this has changed over time, I use only the top outlets to track partisan references across each year since 2010. Like the trust gaps in viewers, there is a strong preference for FOX among republican members of Congress looking to push viewers to favorable content. This FOX bump has

existed since the start of the data and has one grown larger over time. Perhaps surprisingly to those who consider CNN more left wing or “lamesteam”, this outlet was the second most referenced in GOP e-newsletters for the past decade, and it was not until right around 2016 that Republican legislators began lambasting the outlet in e-newsletters, though that behavior is not universal. For Democrats pushing to TV news has always been a less frequent communication tactic. This may be due to the more differentiated media market for traditionally democratic audiences. However, there is one source that has grown in attention overtime, National Public Radio (NPR). After 2014 NPR has followed an upward, near linear trajectory for congressional Democrats.

As PEW and others have reported, this division extends to radio, newspaper and online media, with Republican media consumers preferring places like Breitbart, Rush Limbaugh, and Sean Hannity while Democratic consumers gravitate towards the New York Times, Washington Post, and the Huffington Post more than their conservative counterparts. In congressional communications the story is similar, but there are meaningful differences. The radio pundits Rush Limbaugh and Sean Hannity have plenty of followers in the general public, but are very rarely talked about in congressional e-newsletters. The following ten year totals by party show what non-TV media legislators use in official communications.

Of the major newspapers, the Wall Street Journal is most often referred to in Republican e-news, while the New York Times is most often used in those sent by Democrats. Though as established papers, a good number of members from both push information from these outlets to constituents. The Washington Post tends to have a more liberal readership skew and while more Democrats sent information from the paper, many Republicans did so as well. Republicans urged far more people to look at Washington Post stories than ones coming from the New York Times.

Turning to smaller media, Politico is referenced in very similar numbers by both Republicans and Democrats. But beyond this point the remaining media referenced in official communications diverges starkly along partisan lines. Republicans send stories from The Washington Examiner, The Daily Caller, and the NY Post, while hardly any Democrats ever include content from these outlets. The conservative darling, Breitbart does enjoy one sided emphasis from Republicans in Congress, but interestingly the liberal leaning Vox is used even more often in Democratic communications.

These results, coming from the politician side of things both confirm and add to our understanding of how audience-media political echo chambers exist. The past 10 years confirm that FOX is far away as the leader in political news from a production consumption, and governmentally advocated stance. There are also clear partisan distinctions among efforts to reproduce media coverage, but some platforms — specifically radio — are far more popular with general audiences than they are as sources members of Congress look to guide constituents towards.

Is there anything to be done on the governing side once the new congress is sworn in? Probably not, franking guidelines for these communications only prohibit the outright solicitation of votes or money but legislators are free to bombard constituent inboxes with favorable media all they want. This is system that we’re all in and a set of feedback loop mechanisms that seem to become perpetually sharper and more divisive.



Lindsey Cormack

Associate professor of political science working on equipping people with civic power & understanding political communication