The POD is that Nixon dies in office in early 1972. Agnew is considered too vunerable, so he draws primary opponents including Reagan. The Dems still nominate McGovern, so Reagan wins in a landslide.
I see harder line in Vietnam and against the Soviets, attempts to cut the domestic budget ad mabe taxes (though supply side economics that Reagan favored was still in the future), and a more well funded space program.
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