It's a hit: "Over 38 million Americans watched TV coverage of Barack Obama accepting his party's nomination for president on Thursday, far more than tuned in for the acceptance speeches of past Democratic contenders." How many of these viewers were watching Obama for the first time? Did they like what they saw? How many were voters who have already made up their minds? The answers to such questions are not clear. But it is likely that the Obama bounce is about to bounce a little higher.