I doubt that "poor people" (whatever that means) are the deciding factor in presidential elections. Regardless of who runs, most Democrats vote for Democrats and most Republicans vote for Republicans. The swing voters are independents, Reagan Democrats, Catholics, disenchanted Republicans, some minorities to a degree, etc.
If the economy tanks because of the largest spending bill in history, Obama is done. He can try and blame Dubya, but the blame will lie squarely at the feet of this this massive bill that no one has read.
I'm just astounded that this thing was rammed through without anyone ever reading it. Not a month into his campaign he has rolled the dice. If the economy recovers and is prosperous in 2010 and 2012, he will coast to reelection. If it doesn't, he'll be a one-term president.