For starters Washington DC could be a state in it own right
One of the oddities of US politics is that those who live in the capitol, Washington DC, are rated as second class citizens when it comes to elections. For they are unable to have voting representatives in the House and the Senate as is reflected in the slogan on car registration plates – see above.
It used to be even worse than that and DC residents were not allowed to participate in Presidential elections but since the 1960s DC has the same number of electoral college votes as the smallest state in the union.
But there are strong moves afoot to remedy this and only four months ago the House agreed a move to give full statehood to the area. But this was only going to get through if the Dems controlled the Senate. That might all change after next Tuesday.
For the reason why this anomaly has been allowed to continue is that if DC became a state it would be able to elect two senators and the city is very much a Democratic stronghold. That would alter the balance something that wasn’t going to find favour with the Republicans or Mr. Trump.
If this actually happens then the US territory of Puerto Rico could be next in line possibly with DC increasing Democratic representation in the Senate to four in a body which would then have 104 members each serving six year terms.
The ultra-partisan way that the Senate Republicans have operated has made it more likely that this could happen if the Democrats have the victory that looks likely at the moment.
Smarkets have a market on this on which I have has a small bet.