Five Northeastern states hold their primaries today: New York, Pennsylvania, Delaware, Rhode Island and Connecticut will each hold contests, with a total of 231 delegates at stake.
Before Rick Santorum dropped out of the race, polling had indicated that Romney was the strong favorite in these contests - the only truly close contest was of course Santorum's home state of Pennsylvania.
After Santorum dropped out of the race, all of these primaries ceased to be contested. Romney is likely to walk away with at least a strong majority of the delegates, possibly all of them. Still, there are several important things to watch in today's battles.
1.) How many delegates will Romney win?
Although Romney is his party's presumptive nominee, he is still several hundred delegates shy of the 1,144 he needs to officially clinch his parties nomination. Romney has amassed 697 delegates so far, according to ABC News' projections.
In Tuesday's contest, the most delegate rich state is New York with its 95 delegates. There are 72 delegates at stake in Pennsylvania, 28 in Connecticut, 19 in Rhode Island and 17 in Delaware. Delaware awards their delegates on a winner-take-all scheme, but the other states are proportional, meaning there is opportunity for Newt Gingrich and or Ron Paul to pick up a couple of delegates here or there. Will Romney carry all 231? Or will he end up sharing a small part of the lot?
2.) Will Gingrich pick up a bounce after Santorum's exit?
Back in January Newt Gingrich encouraged Santorum to drop out of the race and endorse him. The logic behind the encouragement, aside from wanting to narrow down the field, was that Santorum supporters would be more likely to back Gingrich over Romney - that Gingrich and Santorum were splitting the more conservative base of the party. This theory has been floated throughout the primary season: If either candidate were to drop out and endorse the other, it would benefit the remaining candidate. There are no hard numbers to back it up the suspicion, however.
Santorum hasn't endorsed anyone in the race, and the talk of his endorsement so far has been centered on a possible Romney endorsement, not a Gingrich endorsement. But Tuesday's primary offers a chance to see whether Gingrich can in fact benefit from Santorum's departure in any way.
3.) Will Santorum still get a percentage of the vote?
Although he suspended his campaign weeks ago, Rick Santorum's name remains on the ballot in all five of these primaries, so technically speaking there's nothing to stop dedicated supporters from checking his name.