I get the feeling that some on this forum may remember the super unpopular Bush from late 2007-2008 but not the Bush from late 2001-2004 that routinely had approval ratings in the 60-80 percent range.
I just remember thinking he would have a hard time because he almost lost the first time and people were struggling after 9/11 and the IT bubble.
Afterwards, I thought he won because his religious stuff was really popular but it turned out in retrospect that the opposition couldn’t get their story straight on the war and people still thought it was going to end soon and well.
A lot of people thought that Trump was going to get the same benefit of the doubt and the way Republicans overperformed tended to show that. Or it could be that the incumbent ground game normally produces a few million extra voters.