TL;DR - 2020 would resolve NO because of the January 6 insurrection.
For this question, "states" includes DC since it also votes for President, and "the actual result" is that declared by credible news media.
This question is a conjunction of all of the following:
in each state, polling places open normally, everywhere they're usually set up, plus mail-in/drop box voting where applicable;
in each state, votes are able to be cast normally and they're all included in the count;
in each state, the officially proclaimed result of the vote matches the actual one;
in each state, at least 50% of electoral votes are cast for the correct winner, according to its law and the actual result;
the candidate that would get the nationwide majority of electoral votes if there were no faithless electors, according to the actual result, actually gets a majority of electoral votes;
Congress certifies as winner the winner according to the actual result;
the winner gets inaugurated on January 20 and effectively acts as President;
none of these steps are threatened or disrupted by significant violence.
The assault on the Capitol on January 6, 2021 would mean that election did not happen "normally", by this question's criteria. Credible news reports will be used to ascertain the outcome of this question.
Minor flaws such as a limited number of polling places opening late due to malfunctioning voting machines, or deviations from normality that are not related to a deliberate derailing of the process, for example the President-elect failing to be inaugurated on January 20 due to sickness, are not enough to resolve this as NO.
I will not trade in this market.
1,000@kgello that's a good question. If I had to resolve this market with regards to that election, I'd say there wasn't an "actual result". Almost certainly, more people cast their votes for Gore than Bush in Florida - the state's results had negative votes for Gore in some areas. So I don't think a credible result could have been established.
I wrote on [another market](https://manifold.markets/BlueDragon/if-elected-will-president-trump-suc#uvlhv0f67un), before polls closing: I do think there's a chance of election rules changing, legitimately or less so. I'll consider normality based on legitimate changes, and legitimacy is determined by the same rules as the market itself. (So like if US citizens are prevented from voting due to being deported that's not normal.)