Many election projections give President Obama a slight edge over GOP rival Mitt Romney heading toward November. And the conventional wisdom is that the vote will hinge on which candidate does better in perennial battleground states, such as Florida and Ohio, and in states where Obama could slip after winning narrowly in 2008, such as North Carolina and Virginia. But after Democrats went down in flames in this week's recall vote in traditionally blue Wisconsin, political handicappers are beginning to wonder whether some states that the president won by larger margins four years ago could slide from Obama's column to Romney's. Here, three blue states that could be up for grabs in November:

1. Wisconsin

The last Republican presidential candidate to win the Badger State was Ronald Reagan in 1984 and Obama took it in 2008 by 14 points, but Gov. Scott Walker's decisive victory in his recall election gave Team Romney new hope. Tuesday's recall fight erupted over Walker's push to strip public-sector unions of their bargaining power, which he says is necessary to repair the state budget, and Walker's victory was seen as an endorsement of the Republican's "aggressive governing style" and commitment to fiscal belt-tightening, says Thomas Beaumont for the Associated Press. If Romney can convince the state's voters that he'll take the same approach in Washington, he has "a reason to feel optimistic about his chances." Don't be so sure, says Dave Cieslewicz at Isthmus. Many Obama backers voted for Walker out of "a sense of fairness," figuring that he should be allowed to finish his term. "Wisconsin continues to be a progressive and independent state, not a conservative Republican stronghold."

2. Michigan

"For Romney, mobilizing blue-collar victims of the recession is essential to victory in November," says David J. Lynch at Bloomberg. Those voters are drifting away from Obama, which might account for the latest "spit-take inducing poll" out of reliably blue Michigan (which Obama won by 17 points in 2008), where white working-class voters make up more than half of the electorate. Late last month, Obama had a 53-39 advantage over Romney in Michigan, the state where Romney was born and his late father served as governor. But a new poll shows a dead heat. "What changed?" asks Alana Goodman at Commentary. "It's likely the latest jobs numbers and poor economic news." Plus, anti-Obama attack ads have been blanketing the state, courtesy of pro-Romney super PACs, says Rachel Weiner at The Washington Post. "Obama and his allies meanwhile, are not on the air at all — although if more polls like this one come out, that might change."

3. Pennsylvania

Pennsylvania's "chronically off-message" Democratic former governor, Ed Rendell, now says his state is "definitely in play," says Charles Mahtesian at Politico, arguing that the race will hinge on who can win the purple Philadelphia suburbs. But Rendell might want to check his numbers, says Mahtesian. Romney trails Obama by 23 points in the counties around Philly. And even if the state could tip red, "the cost and the odds of winning — remember, the GOP hasn't won the state since 1988" — suggest it's a bad place for Romney to spend his campaign resources. (Obama won the state by 10 points in 2008.) "If I were advising Romney," says TWB at Wizbang, "I'd spend the money that he would spend in Pennsylvania in Wisconsin and Michigan. A two for the price of one deal."

Read more political coverage at The Week's 2012 Election Center.