It makes fine political sense to stand against a bill thats as plainly unpopular as this one is.
There's no excuse for any republican to support it.
That was working assumption during the Gingrich shut down as well - polling showed that Americans were disgusted with the current levels of government spending and the presumed waste, experiment demonstrated that Americans were even more disgusted with its absence.
It appears to me that Republicans are likely in a similar situation today: everyone is unhappy with some provision of this bill, but on the average Americans are going to be even more unhappy if nothing is passed at all.
IMO from the Republican standpoint this hand is just about played out - some substantial tax concessions were achieved in the House, probably $50 billion in spending cuts to programs unpopular with most Republicans will take place in the Senate.
But Obama is correct about this much: Republicans lost the last two elections, and to believe that you are going to get the same stimulus bill that you would have from the previous administration, or likely even from a McCain administration, and holding out for anything like it at this time is likely going to extract a political cost far in excess of any likely gain.
It's on to the next deal, folks.