Other than those who suffer from Bush Derangement Syndrome, I don't think voters are going to blame President Bush for high gas prices (he recinded the Executive ban on off shore drilling), they are going to blame the Pelosi 'Rats who went off to recess for 5 weeks and refuse to allow an up or down vote on drilling.
Something like 85% of Americans support drilling, so I think this is one issue they are paying attention to.