Remember that the income or lack thereof in Puerto Rico is very low, hence not much of an income tax problem, remember 47% of American workers pay no income tax.
Puerto Rico, if admitted, would become the 30th most populus State.
This means that there is little chance of Congress admitting them into the Union, they would be a financial burden and would receive more "federal funds" than 20 States and all of the other territories.
Puerto Rico can enter if Texas can split into 4 states.
Given how much we already spend on Puerto Rico I don’t really see giving them statehood as costing much money. Of course the place is poor as dirt, so they won’t contribute much, and they’ll make the unemployment numbers even worse. So in the end I doubt Congress will do it, neither party wants to inherit those numbers, but I still don’t get why PR even wants it, they get all the best parts of being in America without the bill now, don’t fix what ain’t broke.