I wouldn't say he was the most hated to win. I'm not sure he was THAT hated. He seemed to most to be a decent man with good intentions (even if they often led in bad places) and Presidents in war time efforts usually get a boost
You sound like you are saying that with 10 years of hindsight. My hatred for Bush has died down quite a bit since he left office. But in 2004, I hated that SOB, Cheney was even worse. Bush hatred in 2004, was not some extreme leftist thing, it was mainstream in the Democratic party.