He's running for a seat in the House of Representatives. Opponents cry that he got drunk and hooked up on reality TV. Sean Duffy says his reality-TV past won't hurt him in the race.

And he could be right.

Duffy, 38, former star of MTV's The Real World: Boston, is a Republican running for a House seat in Wisconsin's Seventh District, a seat that has been Democratic for 41 years.

Sensing a possible gain in the madly contentious November midterm elections, the GOP is backing him big time. Sarah Palin has endorsed him. The tea party has raised its cup to him. A crack fund-raiser, Duffy has qualified for the top tier of Republican "Young Guns," candidates eligible for extra bucks.

The race is a referendum, not only on the Obama presidency, but also on reality TV and celebrity itself.

"Voters have embraced celebrity," says Robert Schmuhl, a political science professor at Notre Dame University, "which allows a person to get involved in politics without paying a price for whatever might have happened in the past."

Now a district attorney in Ashland County, Wis., Duffy was a regular in season six of Real World: Boston in 1997. A record-holding competitive lumberjack, he competed and was a commentator on ESPN's Great Outdoor Games. He is married to reality-TV vet Rachel Campos-Duffy of The Real World: San Francisco. She has also been a guest host on ABC's The View.

In July 2009, Duffy announced that he would run for the seat held by Democrat David Obey since 1970. Then, surprise: This spring, Obey, one of the most powerful princes of the House, announced he would not seek reelection, making national news and rocking Capitol Hill.

Duffy took credit for Obey's retirement, and what was once a fairly sure Democratic seat is now a real battle.

"For the first time in decades, the Republicans are fired up," says Dennis Riley, professor of political science at the University of Wisconsin-Stevens Point. "He's young and charismatic. I have students here willing to do anything for him."

Reality-TV stars have run for office before. Will Mega, of CBS's Big Brother, lost his bid in May for the Democratic nomination in Pennsylvania's 192d House District. Landon Dais joined BET's Harlem Heights to gain momentum for a Harlem council seat; he narrowly lost. Kwame Smalls, star of VH1's I Love New York 2 (and managed by Omarosa Manigault-Stallworth, star of The Apprentice), got knocked off the ballot for a New York City Council seat last year.

Duffy is after bigger game. He wants to be among a tide of Republican candidates who take back Congress from the Democratic Party, which stunned the GOP in 2008.

Duffy still must win the GOP nomination, and Wisconsin's primaries aren't until Sept. 14, when his opponent will be - the forester vs. the sod-buster! - farmer Dan Mielke. Should Duffy prevail, he would square off for six exciting weeks against the Democratic nominee, likely to be State Sen. Julie Lassa.

Will reality TV be an issue in the campaign?

Yup, says the Democratic Party of Wisconsin. "For years, Duffy has been marketing himself as a reality-TV star," says party spokesman Graeme Zielinski. "He was going around to GOP conventions, and when they heard 'MTV Real World,' they thought, 'We have to jump at this guy; he's cool with the kids.' He got drunk and had sex on TV, and they think this has youth appeal. What did they do on that show - pass around balloons with their chins?"

A beer-drinking, good-guy past may work for Duffy. It suits the culture of Wisconsin's Northwoods, the "jackpine savage" life of "drinkin' beer and shootin' deer."

No one's going to say that aloud; no one needs to. Duffy did drink and horse around on TV, but that's reality. As for hooking up, his closest encounter was with Campos, whom he ended up marrying. But a video trail is a video trail: The Mielke campaign has posted videos on YouTube attacking Duffy for various antics on TV and in the mockumentary The Wedding Video.

Riley, the political scientist, says Duffy "hasn't been hiding the reality TV or the lumberjacking - other people bring that up for him. He stresses that he has six kids, favors a balanced budget, and is running against Congress."

Duffy says he doesn't think it matters: "I believe people don't care about reality TV 15 years ago. They care about reality today. If my opponents want to run on that issue, have at it. I spent 15 months doing reality TV 15 years ago, and that was a very small part of my life." Asked whether he's seen much interest in it among prospective voters, he says, "No one but the media cares about reality TV."

Schmuhl agrees that Duffy's colorful past might actually help: "The borders between participating in politics and the media have become so porous in recent years it doesn't really seem out of the ordinary for a reality-TV person to run for elective office."

Duffy can take heart from the example of Scott Brown. In the Massachusetts senatorial election, Brown's 1982 Cosmo centerfold, with strategically placed forearm, did not prevent him from trouncing his opponent and taking a Senate seat once a Democratic cinch. His nakedness cast Brown as a likable Adam.

And an outsider. This year, a track record in politics may be poison. A celeb past, says Schmuhl, "can work as an asset - while actual experience in legislation and government is a liability. We used to ask of candidates, 'What has this person done?' Today we ask, 'Who is this person?' "

And if the answer is "a celebrity"? Cool.

Distinctions among entertainment celebrity, athlete, and politician (and Duffy is all three) seem so old-school, so black-and-white. From Ronald Reagan to Sonny Bono, from Jesse Ventura to Arnold Schwarzenegger, any PR is good PR. In the entrepreneurial United States, many see reality TV as just another marketing tool.

Political parties have long courted stars. Especially jocks. On March 7, Ocean County, N.J., Republicans endorsed former Eagle Jon Runyan in his run for the state's Third Congressional District seat. Bill Bradley, basketball genius, was a three-term U.S. senator for New Jersey.

Sports is a kind of reality TV. And so is politics.

It'll be a long, hot political season up north. Duffy says he's ready "to work harder than anyone else." Zielinski says local voters "won't fall for a media-darling D-lister." The voters' voice awaits - at the far end of summer.

Contact staff writer John Timpane at 215-854-4406, jt@phillynews.com, or twitter.com/jtimpane.