Obama Ceiling?

There's been much speculation on Hillary Clinton's surprise upset in New Hampshire. I'll offer up a rather parsimonious explanation. Barack Obama got 36% of the vote in NH, which is almost exactly equal to the 35% percent of the vote he got in the entrance poll of Iowa caucus goers. Even with what was perhaps the most positive press coverage for any candidate in recent history, he ended up with zero bounce. Zilch. Nada. This suggests that Obama has a ceiling, at least among white voters, of about 30-40 percent. In Iowa, this was enough to win because Edwards and Clinton split evenly and the also-rans like Richardson, Biden, and Dodd were there to drain-off some additional non-Obama votes. But in New Hampshire, Dodd and Biden were out, Richardson did a bit worse than in Iowa, and, most importantly, Clinton managed to beat Edwards by 22 points (39 percent to 17). Had Edwards been able to split the non-Obama vote with Clinton, the result would have been 28 percent for Edwards, 28 percent for Clinton, and 36 percent for Obama--almost exactly the same result as Iowa. If this is true, rather than Edwards and Obama splitting the "change" vote in Clinton's favor, Edwards and Clinton are splitting the white vote in Obama's favor.