Neither Bush Sr. nor, for that matter, Dole ever sounded like they really wanted to be president. Bush Sr. rode Reagan's coattails against a fairly weak opponent, then (IMO) blew his Gulf War lead in (a) charisma and (b) not understanding the things he needed to campaign about.
Dole was just a terrible candidate, especially against an opponent who was more Teflon than Reagan himself. Shoot, just about any other Republican and I'd have voted for more than a couple other Democrats myself.