There is a movement afoot to make P.R. a state. Notice the wording here, make. Normally the U.S. does not annex territories into itself, but waits until the territory requests to join the union. OTOH, the U.S. is doing a lot of things it doesn't normally do.
The Puerto Ricans have had statehood referendums in the past, and have rejected them, usually by reasonable margins. The reason for this is that P.R. enjoys many of the benefits, such as trade and welfare benefits, that states enjoy, but is free of a lot of federal meddling in the local affairs. Thus when the question is "Shall Puerto Rico petition for statehood?" the answer has always been "no".
The technique to be used this time is the sort of thing the Corlione family would love, and works like this. First the Puerto Ricians will be offered a choice. Shall our status regarding the U.S. remain the same, or shall we pursue something else? Phrased like this, the "something else" option has a great chance of passing. Should the "something else" option pass, another referendum will be presented, with only two options: Statehood or independence. An offer of statehood you can't easily refuse.
The administration fully expects that the six new Representatives and 2 new Senators will all have D's after their names, although with its current track record, that could turn out different.