The perception of Iraq was that it was the right decision but things were going poorly. Remember the majority of ppl who said Iraq was the most important issue voted for Kerry. Without Iraq as an issue, I think Bush would've won 53-47.
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Yes, pretty much. I think Iraq was a net drag on Bush at the time. He probably would have won by a bit more if he'd decided not to invade Iraq, and instead simply concentrated on Afghanistan, which was a much more popular war.
An interesting "what if" though would be what would happen if there'd been no 9/11, no Afghan War, and no Iraq War. There's a decent chance that Bush would have lost.