1976: moderately important, to underline that the behavior of Nixon while in office was going to have consequences
1980: it had significant impact after the fact but at the time, two candidates with very different flaws. One was an idealistic but occasionally abrasive guy who didn’t know how to do inside deals, the other was a slick Hollywood-produced image of dubious real substance.
1984: Umm, no. The Democratic party was running Carter’s VP, for no discernable reasons other than it was his turn.
1988: Not really. Don’t get me wrong, I was very unhappy with the Republicans by this point and wanted to see them ousted, but I remember acid-tripping on election day and realizing that George H W Bush wasn’t going to destroy the country. He held a lot of policy beliefs I didn’t agree with but he was a responsible politician.
1992: Somewhat. Mostly because the Republicans had come to think of Carter’s one term as an anomaly, caused by Nixon’s arrogant lawbreaking and nothing else, and they were thinking of the White House as permanently their own. Since Johnson they’d had it for Nixon’s + Ford’s 8 years, missed Carter’s 4, then for Reagan’s 8 and Bush’s 4-so-far. But once again, Bush wasn’t evil incarnate or anything.
1996: Somewhat. Mostly because the Republicans had decided that by golly yeah, the White House naturally belonged to them, and had thrown everything including a misbegotten impeachment. But Dole, too, would not have been a menace or anything, it was more that the Republican brand was getting to be worrisome.
2000: Meh. G. W. Bush wanted to withdraw the US from the national stage (and quit firing cruise missiles to hit some camel in the ass), bit of a nonintellectual jerk, but although there were policy issues at stake it didn’t seem at the time to be world-changing.
2004: Oh God yeah. Bush had invaded a country for no good reason and we had to reject that by rejecting him. It was important. He hadn’t just invaded Iraq on pretext, he’d orchestrated it very badly and squandered international good will and was incompetent and needed to be ousted.
2008: Important, to try to undo the damages done by 8 years of Bush. And get someone other than a white male in office, finally.
2012: Meh. Romney didn’t warm me up, but, like George H. W. Bush, was an adult and would not be a menace in office or anything. It didn’t seem likely to happen—Obama was in the lead throughout.
2016: Oh my fucking God. Serious shit. We absolutely can’t elect that knuckle-dragging crass moron. And we can put someone other than a male in office, finally. And she’s very competent and able to do the inside deals thingie.
2020: Oh my fucking God squared to the nth power. Let’s have a referendum on whether there should continue to be a US in any meaningful sense?