Tagged: GOP

(Revised at 2:03 pm ET with new Ron Paul-Pennsylvania material.)

The contest for the Republican presidential nomination may be over for all practical purposes, with Mitt Romney the all-but-certain GOP nominee. But that doesn't mean there's nothing of interest in Tuesday's primaries.

Voters are going to polls in Pennsylvania, Rhode Island, Connecticut, Delaware and New York, though turnout is expected to be low. Still, here are four things to watch for.

Nothing about what happens during today's Republican presidential primaries in five states is expected to change the fact that Mitt Romney is the presumptive/expected/presumed/inevitable (pick your favorite word) nominee.

Polls are open in Connecticut, Delaware, New York, Pennsylvania and Rhode Island. There are 209 convention delegates at stake and Romney could pull off a five-state sweep.

But — and there's always a but — there's this:

Ahead of Pennsylvania's primary Tuesday, the likely Republican presidential nominee has been campaigning in the state with a man at the center of running-mate speculation — Florida Sen. Marco Rubio. But Mitt Romney hasn't said much about whom he might name as his vice presidential choice.

Romney has said he appointed a longtime aide to handle the process and that he hasn't yet discussed making a list of potential candidates. But just about everyone else in politics is discussing it. And the men at the top of that list are asked about it a lot.

Republican presidential candidate Mitt Romney campaigned outside of Philadelphia and Pittsburgh on Monday, a day before Pennsylvania and four other states hold their primary contests.

Romney isn't concerned about the primary, but Pennsylvania will likely be an important swing state in the general election. And Monday also offered a chance to audition a potential running mate: Florida Sen. Marco Rubio.