nixon was already in his second term so the only presidency it might have affected would have been ford's. if watergate doesn't happen, agnew doesn't resign and ford isn't appointed VP and eventually president. i guess ford could have run for the nomination in '76 but he would most likely have had to fight a challenge from both agnew and reagan. carter would probably still have been the democrats' choice, but then it all depends on how nixon would end his second term as to who would have been elected in '76.I started a thread a year back insisting that if Henry Starling was one of Nixon's "plumbers" then Watergate would never have happened, which would have tabled Ford and Carters presidencies in favour of a second term for Nixon.
It's a very different Earth in Futures End.