Yes, and of course lots of dead people voted in the election ...
It works like this:
145,000,000 people voted in the election.
Death rate in the US is 867.8 per 100,000
So, we can expect around 3447 people to die the day after casting their vote.
A lot of people, maybe around half the population, voted by mail before election day.
A few thousand of them will die in the period between their visit to the post box and election day.
Whether their vote can still be counted depends on the rules in that state, but either way, it is not fraud.
Also, none of the states are so close that it would affect the final results in any way, even if all the almost-dead voters chose the same candidate.