Isn't there a lot of political pushback against a 51st state? My understanding is that both parties are fairly invested in the 100 member Senate with the Veep as a tiebreaker.
Both sides support it. Or, at least, they've said that they do. That may change once the petition is real... It took Alaska and Hawaii 10 years of fighting to get in. But Obama and Romney both made a point of saying that they would make it happen in the next 4 years if a majority of Puerto Ricans voted it in.
Now...what is a majority? Obama may hesitate because it wasn't very overwhelming. Even more complicated, the pro-statehood governor got voted out and the anti-statehood guy got voted in. So that may be an excuse.
But, in the past, once we get to this point there's nowhere to go but forward.
Don't get confused by our local statehood woes. DC's problem is much more complicated.