It is interesting to see how you have the spark of mind to include this option back in december 2019.
The BLM / Floyd situation (not yet resolved) is a little bit early in the year to have an impact on the November elections (ie cancel them).
But who knows.... maybe more riots for later in the years (BLM or other social issues) and the martial law might be invoked.
As you can see by the reference to Martians I wasn't particularly serious about that possibility back then but with Trump's authoritarian leanings I think there's a non-zero chance of him trying to push the election around if he sees it not going his way. Rioting provides a good excuse it's just that it might not last until November. However... given the year we're having there could well be some other crisis or two at the convenient time. Even friggin' Martians are probably looking at this shit and thinking "let's just put face masks on and invade, nobody will see it coming".