Democratic National Committee Chairman Howard Dean told Tim Russert last Sunday on "Meet the Press" that undecided superdelegates will ultimately "vote for the person they think can beat John McCain." That sounds like a reasonable standard, but how do you measure it?
1. The Best Matchup vs. McCain In National Polling: Looking at Pollster.com's trend lines and the RealClearPolitics polling average, it's clear that neither Democrat has a decisive advantage. Pollster.com shows Hillary Clinton leading McCain by 2 points, while Barack Obama is ahead by one point. The RealClearPolitics average of polls taken April 17-April 29 shows Obama leading McCain by 1 percent and Clinton beating the Arizona senator by 3 percent.
Pollsters will tell you that national polls are good at measuring trends, like how certain demographic groups view the candidates or which issues are becoming more or less important. But for pure horse-race matchups, state polls are much more effective.
2. The Strongest Candidate In State Polling: While the most recent polls from states rich in electoral votes -- such as Ohio and Pennsylvania -- show Clinton running stronger than Obama against McCain, Obama does much better in swing states such as Wisconsin (which John Kerry won in 2004) and Iowa (which Al Gore carried in 2000). And Obama is more likely to put traditionally red states like Colorado and Virginia into play. While both candidates may take different paths to get to the magic number of 270 electoral votes, can anyone confidently say that one path is better than the other? Or that one is safer?
3. The Biggest Downballot Impact: Earlier this year, the consensus among most insiders was that Clinton was going to be more of a burden for House and Senate candidates, especially those running in swing or Republican-leaning districts. Obama, meanwhile, was viewed as better able to expand the playing field or, at the very least, not hurt candidates running in traditionally GOP districts. Democrat Bill Foster, who won the special election last month in former House Speaker Dennis Hastert's very Republican district in exurban Chicago, notably used an Obama endorsement in his TV advertising.
That view seems to have changed in recent weeks. Rep. Tom Cole, chairman of the National Republican Congressional Committee, was quoted last week as saying Obama was "the weaker candidate" of the two and will "give us plenty of ideological divisions to work with." In special elections in Louisiana's 6th District and Mississippi's 1st District, Republicans are trying to link the Democratic nominee to Obama, not Clinton, in their attack ads.
Even so, one Democratic strategist who works in a number of swing districts revealed in an interview that he'd rather have Obama on top of the ticket this fall. The reason? Even though Obama's image has taken a serious beating over the last week or so, it is still more malleable than Clinton's. The New York senator has an image that's set in stone. Clinton has a narrow trading range -- a low ceiling, but also a high floor. Obama, on the other hand, has what looks to be a limitless ceiling, but also a bottomless floor.
Is it fair to assume that Obama would be any more of a burden in swing districts than, say, Gore or Kerry? If Democrats win in La.-06 or Miss.-01, will that allow the Obama campaign to shoot down the theory that he'd be an anchor around the necks of Southern Democrats?
In the end, delegates are destiny. Democratic insiders seem loathe to hand the nomination to the candidate who hasn't won the most delegates -- especially since the "electability" argument is so difficult to gauge, leaving both the ultimate nominee and runner-up with valid arguments for who'd be the strongest candidate in November.