At least do some research.
The Democratic Party (well, it's currently dominant faction, at least) is also center right.
> If Puerto Rico were to join as a state you'd more likely than not find its politicians trying to retain their own party ties.
There'd be strong pressure to fuse with or be displaced by the national parties once PR was involved in Congress and, more importantly, Presidential elections; the days of states having distinct local major parties on a lasting basis likely ended when the Minnesota Farmer-Labor Party aligned with the national Democratic Party, and the nationalization (and globalization) of the media, combined with the way electoral politics works means that's unlikely to change even with the admission of new states with pre-existing party systems.
Besides that, it's really hard to believe that even Puerto Ricans with conservative views are going to break in significant numbers for a party that seems to be so hostile to them.