Mitt's bump (or, fickle Americans)

Mitt won the first debate--66 percent of people polled agree, and the remaining 34 percent are delusional.  He won not because of the strength of his argument, but because of strong delivery.  And after the debate, his standings in the polls jumped.  I haven't heard many discussions about causality, but the obvious conclusion is that image matters more than content.  Before the debate people knew the platforms of Republicans vs Democrats--big business vs big government; guns vs butter; drill-baby-drill vs stewardship; vouchers vs public schools; imposed bedroom values and voluntary charity vs marry-who-you-will and imposed charity--the debate wasn't terribly enlightening regarding policy.  It's hard for me to understand how undecided voters could make a choice based primarily on speaking performance when the differences in values are pretty stark.  But maybe--and I find this explanation both reasonable and hopeful--the bump in the polls is less about values than about likeliness to vote.  In other words, based on the debate, maybe right-leaning undecided voters are now more likely to vote than left-leaning undecided voters.  Part of me (the Mormon part) was glad to see a strong performance by Mitt; I just hope President Obama shows up for the next debate and can inspire people as he did 4 years ago.