We've already taken it on, it's part of the U.S. and we already spend a ton of federal money there. The bigger issue is 2 reliably democratic senators and a 4-5 person reliably democratic house delegation and 4-5 electoral votes. If DC can't get representation and they pay full taxes (remember that whole taxation without representation thing that the real tea party was about, guess we ignore it if it might cause the current "tea party" to lose some power), then PR which actually does have some federal tax shielding doesn't have a chance. Then there's Guam and CNMI to consider, another reliably democratic block. If we actually added all 4 as states Republican's would be history, so something tells me they will do nearly anything to avoid starting down that slippery slope.
This is, I believe , spot on! Puerto Rico, regardless of how they vote in their upcoming referendum, will not become the 51st State.