Yes but I also think they should get to vote in general elections.
RIP Republicans if that were the case.
Normally we admit States as an ideologically contrasting pair (I.E. Alaska and Hawaii, though there roles at the time were reversed), so if it got to that point, Guam would most likely be admitted as well, and they are currently solidly Republican.
Yes, Puerto Rico, the U.S. Virgin Islands, Guam, and American Samoa could all be admitted as a group. Puerto Rico would be Likely D but not impossible for a Hispanic-friendly R to carry, the U.S. Virgin Islands are majority black, so Safe D, Guam is heavily military and military-industrial complex, so Likely R, and American Samoa is majority Mormon, so Safe R. However, Puerto Rico is about the size of CT and would get 5 CDs this decade, while the other 3 are all smaller than WY, so it would help Democrats in the electoral college and in the House (provided there's no concentrated local R strength in PR), but enhance the Republican tilt of the Senate.
///northern mariana islands
Oops. It appears to be heavily Republican and also less populous than WY, so admitting all 5 as states could be a decent deal for both Democrats and Republicans. The former get several safe-ish EV and house seats out of PR, while the latter presumably get 6 of the 10 senate seats and are only down 10/9 in total EV.
Eh, I think they'd all probably end up swingy at best and quite possibly all solid D. The national parties have little influence in the territories, so I doubt recent election results indicate much about how they'd ultimately vote as states. The Democrats' broad success with almost all racial minorities and in Hawaii makes me suspect they'd probably vote D.