Covid-19 is seasonal, which means that cases and deaths might follow the seasonal pattern of cases of the type of coronavirus that causes colds, with lows in June through September, and increases as the days progress through October, November, and December. Like So:
And this might effect the U.S. Presidential Election of Nov. 2020. As the pandemic suddenly worsens in October and early November, people (not realizing this is merely the usual pattern of a seasonal disease) will blame the government and the current president, Donald Trump. This could weigh against him rather substantially.
I dare say that if the election were held in early October, Trump would be much more likely to win, and if it were delayed until early December, he would be much more likely to lose.