More House Republicans send messages on Twitter than Democrats, according to figures compiled by students at Northwestern University's Medill School of Journalism.

The Medill students compiled a look at how members of Congress use social media and found that 86 percent of House Republicans use the social networking service, compared with 75 percent of House Democrats.

But while more politicians are on Twitter, techPresident has previously reported that they still seem to be having the same conversations they have elsewhere. The Medill students' survey offers some exceptions.

The Medill folks happen to have caught a snapshot of a statistic I've been curious about for quite some time — which members of Congress do the most replying and retweeting. Where their story appeared elsewhere, it did so with interviews from experts in digital congressional correspondence, like iConstituent's Andrew Foxwell, telling them that members of Congress don't do so well at actually engaging people on social media.

According to Tweetstats.com, the tool the Medill crew used, a paltry two percent of House Speaker John Boehner's tweets from his official account are replies to other Twitter users — and then, they're replies to other pols and media outlets like The Detroit News, the National Review Online's Kathryn Lopez, or ABC2020 anchor Chris Cuomo.

There are exceptions to that rule, though — exceptions like Rep. Dana Rohrabacher, Republican of California, or Rep. Steve Pearce, Republican of New Mexico. Both of them top the students' survey of social media use; about 56 percent of Rohrabacher's tweets are replies, according to the survey, while nearly 47 percent of Pearce's Twitter messages are retweets. Among House Democrats, Rep. Jim Cooper (D-Tenn.) has the most retweets, with 34 percent, according to their work.

Rohrabacher certainly uses Twitter to talk to his constituents, including ones with whom he disagrees. According to tweetstats.com, he's talking with a much different crowd than Boehner is — conservative bloggers like Melissa Clouthier, who has around 23,600 Twitter followers, or California native and Anaheim Angels fan Thomas Marchetti. Rohrabacher represents the area around Huntington Beach, Calif., not far from Los Angeles and Anaheim.

Political conversations on social media now are actually even more polarized than conversations elsewhere, we've previously reported. While there's a pretty solid cross-section of the American population on Twitter and Facebook, especially when you take the two together, those folks who choose to talk politics on social media services generally have strongly held views.

At least for now, that is. Congressional staffers are increasingly taking the position that social media is important. In a follow-up email with me, Foxwell said that having more social media managers among members' senior staff could make their Twitter presences less about partisan politics and more about retail politics — the daily constituent service that is bread and butter for any elected official.

"It’s a dream to get a new media director elevated to senior staff with each Member," Foxwell said in an email.