This part of the quote doesn't show up in the transcript. "and you will suddenly realize that you must go to the polls and vote for Obama"
In the part they cut out where he talks about the fact that it's up to him in 20 minutes to make his case and that he's going to try to do so in the time he has. That kind of puts a different context on the epiphany he's seeking and I think the light shining down is just in jest, like when the lightbulb goes off and you go ah-ha! Bush and Rove played the holy angle way more than I've seen from Obama.