Tom Tomorrow crunches the poll numbers so you don't have to:
While Bush’s approval rating is still a bit higher than Nixon’s at a comparable point, his disapproval rating now exceeds or equals that of Nixon’s in every Gallup poll except one. This sole exception is the final poll in July, 1974 just before Nixon left office, when Nixon’s disapproval rating was a single point higher at 66%.
What’s really remarkable is this is WITHOUT any congressional investigation of Bush’s misdeeds, plus an economy far better (as much as it sucks for many) than in summer 1974. So Bush really has nowhere to go but down. This one is going to make sporting history.