Why is the presidential race tied? It's the game everyone is playing. Democrats in particular really want to know the answer to this question. They assume, reasonably, that the underlying political conditions favor their party. They note that the Democrats maintain a sizable lead on the generic ballot. Yet Obama and McCain are running neck and neck. Watching the Democratic convention last night, you got the sense that some Democrats are worried Obama isn't winning handily because he's not considered "American" enough. That's why Michelle Obama stressed the fundamental similarities between her family and her husband's, and their family and all American families. As David Brooks notes today, other Democrats think Obama isn't experienced, aggressive, or populist enough: "It's like a Greatest Misses compilation of every Democratic campaign idea ever conceived." But the simplest explanation is often best. Despite what you may be hearing, America remains a closely divided country. The parties split Americans' loyalties down the middle, give or take a few percentage points. So it doesn't help when the Democrats nominate one of the most liberal tickets in memory. Obama's problem isn't his race, or his cosmopolitanism, or his campaign style. It's his politics. (His youth and inexperience don't help, either.)