Exactly what it says. What kind of effect would it have on Reagan’s presidency if the “October Surprise” theory starts getting legs within serious circles during Reagan’s first term.
Maybe somebody is able to corroborate Bill Casey’s trip to Madrid a decade earlier.
Casey's trip to Madrid was in July of 1980, which can't be "a decade earlier" than any point in Reagan's first term(or his second, for that matter). Do you mean "in the previous decade"(1980 being technically part of the previous decade)?
Anyway, as for Iran-Contra, if the revelations come out in the first term, and there's enough blowback, that might butterly away Iran-contra, since(if my history is right), the events leading to I-C didn't start up until 1985, and Reagan and Co. would probably be paranoid about doing anything too shady in the same part of the world that everyone was then accusing them of doing other shady stuff in.
And that's assuming Reagan wins in 1984, IOW the scandal doesn't butterfly away his re-election. On that point, I do think there is a certain section of the electorate who would think "Sheesh, if a few more weeks for those hostages in Tehran is what it took to stop some weak-minded ninnies from re-electing that commie-traitor Carter, I'd say it was worth it". Especially considering that, by 1983 or so, the hostage-crisis is going to be less about the suffering of real-people, and more just about a vaguely remembered humiliation for the USA.
Though I still think(hope) there would be enough outraged swing voters to toss Reagan out if it were proven that he deliberately prolonged the agony of the hostages for selfish political gain.