The (seemingly impossible to predict) percentage of PDP supporters that would be Republicans seems to be the key to the whole thing.
I wish Puerto Rico had a Presidential preference poll or something, that would be useful data.
Yeah, the percentage of PDP members who wiuld vote Republican if PR was a state could be 20% or 80% or any bumber in between; one would think that the historical ties with the Democrat Party would disappear soon, and that voters who want more local autonomy and lower federal taxes would be more at home in the GOP, but it would be a fool’s errand to make a prediction. We know how well those predictions turned out in 1959 (when AK and HI were admitted pretty much in tandem, since AK surely was going to be a Democrat state so it was only fair that obviously Republican HI be admitted as well).
But we don’t know how many NPP members would be Republican, either (and preference polls won’t help, since they don’t vote for persons running as Democrats or Republicans, except every four years in the presidential primaries).