Obama upsets that equation because of his crossover appeal to independents and moderate Republicans. ~Jacob Weisberg, Slate

This is mostly guesswork.  Hotline does have a FoxNews poll today showing that Obama does marginally better among independents in a match-up against McCain than Clinton does, but he actually does one point worse among Republicans and is five points weaker among Democrats (more become undecided when faced with an Obama-McCain matchup).  So much for the party being excited about him.  The undecideds are six points higher for Obama v. McCain than Clinton v. McCain, which is probably partly a function of so many people not knowing who he is yet.  One possible ray of sunshine for Obama: McCain’s numbers among Republicans go down against Obama (from 78 to 73), as some seem to become undecided when they do not have the obvious hate-figure of Clinton to automatically tell them that they should support McCain.  But right now Obama is mostly a name tied to a smiling, friendly guy who is trying to sell you a book about hope.  He says nice things about faith and even goes to church!  That is bound to improve Obama’s numbers.  Wait until he starts campaigning, and watch those Republican crossover numbers drop and watch the independents flee.