But then it happened again.
Earlier this month, Republican U.S. Rep. Jim Gerlach abandoned his gubernatorial bid and decided to run for re-election in the 6th District. Gerlach instantly became the odds-on favorite for the Republican nomination.
"It's kind of like we found Welch another date and now the girl from the cheerleading team is available," said a Delaware County GOP insider.
It's enough to make even a veteran politician want to throw in the towel. But Welch says that he's not backing down this time. He'll go to the dance stag if he has to.
"People are frustrated with the status quo in Washington," he said. "They're frustrated with both parties and looking for outsiders."
Welch, a wealthy businessman with an engineering degree, says that he won't step aside for Gerlach, even though the battle-tested incumbent appears to have the support of the Republican establishment as he seeks a fifth term in the district, which covers parts of Chester, Montgomery and Berks counties.
Republican strategists say that Welch is congressional-candidate material. He's smart, articulate and technologically savvy. And he already has what candidates are always trying to get their hands on - money.
Welch, who lives in Charlestown Township with his wife and two children, said that he contributed about $650,000 to his campaign through the end of last year, but declined to reveal how much more he's willing to spend. He said that the ability to self-fund a campaign is an advantage because he doesn't have to spend his days dialing for dollars.
"I see it as a positive," he said. "It gives me a lot of time to spend talking with voters and discussing the issues as opposed to fundraising."
Welch, a fiscal conservative, said that he'd fight for small businesses and small government. He wants to "move the decision-making and power closer to the people" and away from Washington.
"Voters dislike Democratic pork as much as they dislike Republican pork," he said. "I think they're looking for leaders that will go down there and clean the place up."
But Welch's past has given Gerlach ample ammunition with which to attack his conservative credentials.
In 2006, Welch voted for Democratic U.S. Rep. Joe Sestak and contributed $300 to his campaign. A longtime Republican, Welch said that he was frustrated with his party at the time, and registered as a Democrat from 2006 until last year.
"Looking back, it clearly was a mistake because I think the Democrats did much worse" running Congress, he said.
What is less widely known, however, is that Welch also voted for Barack Obama in the 2008 presidential primary. He voted for John McCain in the general election.
"It really raises questions as to the seriousness of his ideology," Gerlach said. In the hard-fought 2006 midterms, he said, "a lot of us were on the front lines trying to put forward good Republican values, but he decided to turn to the other party."
Gerlach's early attacks are perhaps a sign that he views Welch - and his money - as a threat. But the congressman said that he's confident that he'll be able to hold off the young challenger in the May primary, should Welch decide to remain in the race.
"I'm a person who has worked all the communities in this district," Gerlach said. "I understand the diversity and the problems of the district."
Welch declined to fire back at Gerlach, dismissing it as the type of political "silliness" that turns off voters.
With three suburban congressional seats in play, Philadelphia-area voters will be bombarded by attack ads this year, fueled by money from the national parties.
The deluge likely will be even more intense than that of 2006, as a result of last week's Supreme Court ruling that lifted restrictions on political advertising by corporations and unions.
"All of the residents of these districts will see many, many more ads than they did even the last time," said Patrick J. Egan, assistant professor of politics and public policy at New York University.
It remains unknown which party will benefit the most from corporations' and labor unions' ability to spend unlimited amounts of money on political ads, Egan said. Corporations tend to support Republicans, while unions typically back Democrats.
Sestak's seat in the Delaware County-based 7th District, which he wrested from longtime Republican U.S. Rep. Curt Weldon in 2006, will be open this year, assuming that Sestak presses on with his campaign against Democratic U.S. Sen. Arlen Specter. Last week, Pennsylvania Democratic Party Chairman T.J. Rooney called on Sestak to run for re-election in the House, but Sestak's campaign said that he still has his sights set on Specter.
In Gerlach's 6th District, recent history has shown that whichever Republican prevails in the primary is likely to have a tough race in November.
And the 8th District race also could be tight this year, creating a replay of the three-way slugfest in the Philly suburbs four years ago. Republican Mike Fitzpatrick, who lost the seat to now-U.S. Rep. Patrick Murphy in 2006 by less than 1 percentage point, announced Saturday that he wants a rematch this year.
In 2006, Democrats won two of the three seats, but some political observers say that the results could be flipped this year if an anti-incumbent electorate expresses its frustration with President Obama and the Democrat-controlled Congress.
Egan sees the potential for confusion among voters in the 8th District, with a congressman named Patrick and a former congressman named Fitzpatrick. The district covers Bucks County and a section of Montgomery County and Northeast Philadelphia.
"The majority of voters pay very little attention to politics and it's quite possible it would be difficult for many voters to remember who the true incumbent is," he said. "It's an amazing recipe for voter confusion, and generally the ads don't necessarily clarify that for voters."