"Obama Vs. Hillary: Who Has The Magic Bullet Needed To Beat Republicans?"

Greg Sargent (TPM Election Central):

One thing that the exchange of barbs between Hillary and Obama at yesterday's Jefferson-Jackson Dinner showed is that one of the deciding factors in the race will be this: Which candidate do voters think has the magic bullet to defeat the Republicans?

Edwards has spent less time claiming he's the one to choose on this score, but it's been a key argument advanced by both Hillary and Obama.

Hillary's case is that she (and Bill) have defeated the Republicans before and hence know what it takes to do it again. As she put it yesterday:

"We must nominate a nominee who has been tested...I know what it’s going to take to win.”

Obama's argument, meanwhile, is basically the liberal blogger argument: He says that you don't look strong by basing your positions on the fear that Republicans will be able to depict you as weak. As he put it yesterday:

"I am running for president because I am sick and tired of Democrats thinking the only way to look tough on national security is by talking and acting and voting like George Bush Republicans."

Clearly both candidates think that this question -- who has the secret formula to defeat the Repubs -- will be a deciding factor. So who's argument is better? Who's right? Which will prove more compelling to voters?