One notable difference between Republican candidate Mitt Romney and President Obama involves their campaigns' social media skills, a recent study shows. Though each side uses digital tools to talk directly with voters, seek donations and rally volunteers, an independent research center found that Obama's team posted nearly four times as much content as Romney's campaign and was active on more platforms.

The president's online content also earned more responses -- twice the number of shares, views and comments, according to the Pew Center's Project for Excellence in Journalism, a neutral group in Washington, D.C., that did a detailed study during June and July of the national campaigns' websites and activity on Facebook, Twitter and YouTube. Separate research issued last week by a different Pew project shows that 36 percent of social network users say the sites are “very important” or “somewhat important” for keeping up with political news.

The main study, released in August, found that Obama's campaign published 614 pieces of content across the three platforms during a two-week study period and Romney's posted 168 items. The gap was the greatest on Twitter, where the Republican campaign averaged one daily tweet, versus 29 from Obama's re-election staff. Obama also produced about twice as many blog posts on his political website as did Romney and more than twice as many YouTube videos. Last week, the president's acceptance speech at the Democratic National Convention set a record for political moments on Twitter -- with 52,756 tweets per minute coming just after its conclusion Thursday night, the company announced. And according to the Nielsen rating service, the Democratic convention drew more viewers than the Republicans each night.

Pew researcher says: "Historically, candidates who are first to exploit changing technology have an advantage." -- Tom Rosenstiel, director of the Project for Excellence in Journalism

Columnist says: "It is too early to say what the Obama campaign’s digital edge will mean on Election Day, but if it can convert virtual engagement into actual turnout, that could turn a tough race into an easy one." -- Charles M. Blow, New York Times

Candidate websites: www.electmitt2012.org and www.barackobama.com