Not necessarily true. They currently have a republican governor. I think we must put an end to the status quo, not only in Puerto Rico but in the other territories as well. All other territories became states at some point so it really doesn't sit well with me that these insular territories have had that status for more than a century in some cases.
Either give them statehood or set them free.
Yes and no. They have a penepe governor who happens to be affiliated with the Republicans. Take statehood/commonwealth out of the picture (which divides the Democratic voters but not the Republican ones) and you have a solidly, solidly Democratic state.
Of course, there would probably be a minor leftist pro-independence party active at the state level. But think Vermont (plus independence, and of course the reasons for voting Democratic or Republican would be very different from Vermonters).
I'm thinking Bronx, not Vermont 
A solid Democratic state doesn't equate to two Democratic senators. Arkansas is a solid republican state and they have two democratic senators. Local politics will always be influenced by factors very different than the ones that determine national politics.
My point is that territories are no different than colonies (you belong to us, but you're not one of us, therefore you cannot vote) and in the year 2008 it's disgraceful that we still have them.
I would disagree that Arkansas is "solidly Republican" (it certainly isn't at anything but the presidential level), but your point is otherwise valid. However, I'd point out that voters tend to be more partisan in Senate races than they are in state and local races.
Poll
