Joe Biden said on “Meet the Press” Sunday that he’ll be “surprised” if the 2002 vote to authorize the use of force in Iraq becomes the “defining issue” in the race for the 2008 Democratic presidential nomination.

He’d better hope that he’s right.

Biden voted to authorize the use of force against Iraq in 2002 — a vote that puts him, at least in hindsight, on the wrong side of the vast majority of Democratic voters. As Knight Ridder notes today, a recent CBS News poll had 77 percent of Democrats saying that it was a mistake for the United States to take military action in Iraq.

Of course, Biden isn’t exactly alone here. Seven of the Democrats considering White House runs in 2008 were in the Senate in 2002, and six of them — Biden, Evan Bayh, Hillary Clinton, Christopher Dodd, John Edwards and John Kerry — voted in favor of authorizing the use of force against Iraq. Among the six, only Edwards has said unequivocally that his vote was a mistake.

Ted Kennedy said Friday that his vote “against this misbegotten war” in 2002 was “the best vote I have cast in the United States Senate since I was elected in 1962.” Tim Russert asked Biden Sunday if he has the same view. Biden’s response: “I, I dont think so. I think misunderstanding this administration is the worst miscalculation Ive ever made in my career.”

It was a Kerry-like equivocation, and it’s the kind of thing we’ll be hearing often as Democratic contenders try to square their 2002 votes with political reality in 2006 and beyond. Feingold doesn’t have to engage in such verbal gymnastics; neither, for that matter, would Al Gore, if he were to run. But so long as centrists like Mark Warner and Hillary Clinton are perceived as the “serious” Democratic contenders — so long as Democrats cluck about Americans’ not being “ready” for a Russ Feingold — a “sorry, my bad” candidate will be the best the Democrats can hope to offer in 2008.

It’s a sad reality, and we aren’t the only ones coming face-to-face with it. In an interview with the Washington Post’s Chris Cillizza, Feingold says that, if he decides not to run or runs and loses, even he may “end up” supporting “someone who in the beginning supported the war.”