Well, not necessarily. It is thought that Gore should have waxed the floor with Bush in 2000 because of the still strong economy. He didn't. Today, polls show that voters haven't given Bush the credit he is due on the economy. Voters may have stopped giving credit for a good economy-- only assigning blame for a bad one. That would make the good economy not as a plus for Bush, but just a neutral factor.
You have to work at being as pessimistic as that, don't you? Is there a class I can attend. I mean, really, I stand in awe.