How many campaign aides does it take to send a single tweet?

According to a study published Friday by a University of North Carolina assistant professor, the answer near the end of Mitt Romney's 2012 presidential campaign was 22: Nearly two dozen staffers had to approve every tweet, Facebook post, blog post, or photo posted by Romney's digital team.

"The digital team unfortunately did not have the opportunity to think of things on their own and post them," said Caitlin Checkett, the campaign's digital integration director, in the study. "The downfall of that of course is as fast as we are moving, it can take a little bit of time to get that approval to happen."

The Romney campaign had a digital team of 16 staffers, compared with the Obama campaign's six-person team that included four staffers, a translator, and a digital director.

"Staffers on both sides of the aisle argue that the Obama campaign's digital team ... had significantly more autonomy," the study found. "This autonomy enabled staffers to respond to political events in the moment and in a communicative style that accords with the norms and expectations of networked publics on Twitter."

The study notes Twitter was mostly a tool for influencing journalists and "an elite core of supporters."

"Most likely not one thing we did on Twitter persuaded any voter or even necessarily reached any undecided voters," Obama digital director Teddy Goff said in the study, but it "reached the somewhat elite core of supporters and then very importantly reached reporters as well."

Goff said staffers "spent a lot of time thinking about how we could sort of manipulate the sort of national dialogue" and that discourse among political elites on Twitter "shaped journalistic perceptions of the race and ultimately how they covered it, much in the same way that informal talk at the bar and campaign bus did during previous cycles."

The study, "Seizing the moment: The presidential campaign's use of Twitter during the 2012 electoral cycle" by Daniel Kreiss, used interviews with staffers from the Romney and Obama campaigns and qualitative content analysis of Twitter feeds.