Wallace vs. Nixon:
Nixon narrowly wins, 283-255. This election would be vital, because the parties would be reversed. The South would become ultra-Democratic again, and blue collar workers in the North would vote heavily Democratic as well. DC and Hawaii would become GOP strongholds, as minorities vote Republican. Wallace would also have done well in the Mountain West. If Wallace had been the nominee, the Democrats would have become the majority party again.
This could easily become an alternate timeline.