Which presidential election had the most uniform state by state results?

[𝕭𝖆𝖕𝖙𝖎𝖘𝖙𝖆 𝕸𝖎𝖓𝖔𝖑𝖆]

In 1960, 18 states went Democratic by less than 7.7% and 13 went Republican by less than 7.7%
In 1976, 18 states went Republican by less than 7.7% and 13 went Democratic by less than 7.7%
In both years on both sides (although less so for Nixon '60), there was a sizable gap between the state that voted Dem (or Rep) by 7 something points and the next state which voted more Dem (or Rep).

1992 had even smaller margins across the board but doesn't fit this well because of the variability of the Perot vote.

For comparison, in 2000 there were 19 states decided by less than 7.7%. In 2004, there were 16 such states. In 2016, just 13!

[𝕭𝖆𝖕𝖙𝖎𝖘𝖙𝖆 𝕸𝖎𝖓𝖔𝖑𝖆]

1960 easily...with the lone exception of Mississippi and it's unpledged slate.

Fun fact: Nixon and Kennedy each carried at least one county in every state.

Yeah, that's the only presidential election in history where it happened, so in some sense 1960 had the broadest playing field for both sides ever.