Correction Appended

Republican candidates for the Senate in the November midterm elections have on average four times as many Facebook fans and five times as many Twitter followers as their Democratic opponents, according to a recent analysis.

HeadCount, a nonpartisan organization that works with musicians to promote voter registration and turnout, tallied fans of each social media profile tied to the candidates’ campaigns.

“The difference was as dramatic as we ever could have imagined,” said Andy Bernstein, the group’s executive director.

Republican Senatorial candidates for the 37 seats in play this year have 1.43 million fans on Facebook pages linked to their campaigns, while Democrats have less than 300,000. On Twitter, Republican Senatorial candidates have close to 520,000 followers and Democrats have less than 90,000, according to the report.

That’s an average of more than 38,700 fans for each Republican candidate and more than 8,200 for each Democrat on Facebook. On Twitter, each Republican averages about 14,000 followers to each Democrat’s roughly 2,500.

“Obviously what you’re talking about there is a base, a motivated base, which is what every candidate wants to have,” Bernstein said. “What I think we’re seeing is just the enthusiasm gap, that social media is a barometer of people’s passion. A considerably higher number of people are enthusiastic and are just feeling personally connected to these candidates.”

The totals are skewed by Sen. John McCain (R-Ariz.), who leads all candidates with more than 680,000 fans. Coming in second and third are Florida GOP candidate Marco Rubio, who has more than 122,000 fans, and Sen. Jim DeMint (R-S.C.), with more than 95,000 fans.

The top Democratic Senatorial candidate on Facebook is Sen. Barbara Boxer (Calif.) with more than 35,300 fans and more than 22,600 Twitter followers. But her opponent, Carly Fiorina, leads all candidates on Twitter with almost 298,500 followers.

HeadCount found that even without McCain’s fans, likely linked to his 2008 presidential run, Republicans still averaged close to 21,000 fans per candidate.

Katie Harbath, director of new media for the National Republican Senatorial Committee, said GOP candidates have been seeking fans and followers and using Facebook advertising to draw them in.

“For us, it is a huge message vehicle to reach people,” she said. “Facebook has now overtaken Google as far as how much traffic it is driving back to our site.”

But translating fans into votes is another matter, especially when many fans may not be in the same state as the candidate, Harbath said.

Republicans can be encouraged by the fact that the winners of most primaries this year had more fans than their opponents, Facebook spokesman Andrew Noyes said. For instance, in the Delaware GOP primary, tea party favorite Christine O’Donnell had more fans than Rep. Mike Castle. In New Hampshire’s GOP race, Kelly Ayotte outpaced Ovide Lamontagne in both fans and votes.

“Tea party candidates are going to do very well with this and it makes perfect sense why,” Bernstein said. “They’re anti-establishment and they’re very good at driving at people’s passions, but it doesn’t mean that every tea party candidate is going to win.”

And in individual competitive races, some Democrats are winning the social media battle. Sen. Russ Feingold (D-Wis.) has a bigger presence on Facebook and Twitter than GOP rival Ron Johnson. Similarly, Sen. Kirsten Gillibrand (D-N.Y.) is outpacing opponent Joseph DioGuardi.

Democratic Senatorial Campaign Committee spokeswoman Deirdre Murphy said, “In our competitive races, Democratic candidates run strong online programs that will continue to grow as Election Day nears.” The Democratic Senatorial Campaign Committee’s Facebook page has more fans than the NRSC page. But on Twitter, the NRSC has more followers than the DSCC.

Correction: Sept. 28, 2010

A Democratic Senatorial Campaign Committee spokeswoman’s name was misspelled. It is Deirdre Murphy.