With a winner yet to be determined in a bunch of states, this race could go either way, and might not end up being all that close in the electoral college. However, it looks to me like the single most likely outcome is a Biden win by 270-268, the narrowest possible margin.
In this scenario, Trump wins Pennsylvania and holds on in North Carolina and Georgia. Biden wins Michigan, Wisconsin, and holds on in Arizona and Nevada.
That leaves the two singletons — one from that congressional district in Maine and the other from Nebraska. It looks like Trump has won the former; Biden the latter.
In this breakdown, Biden wins 270-268.
This specific outcome probably isn’t more likely than not, but it might well be more likely than any other.
This outcome would be difficult to swallow, but would not be at all egregious. The two congressional districts would be a wash, so this oddity wouldn’t have determined the election. Trump will have picked up a vote in a blue state. Biden will have picked up one in a red state.
In addition, Biden looks to have won the popular vote. If Trump fails to draw an inside straight this time, that doesn’t mean the election was unfair.
This isn’t to say that the president won’t have valid grievances. If Trump looks to have lost one or more states due to fraud — a definite possibility — he (we) will have good grounds to complain. But the electoral college system itself won’t have been unfair to Trump.