When they drop out and endorse Romney, do those delegates have to go to him or do they become unbound?
I assure you the GOP will bend rules to suit their needs.
1,144 are needed but there are 2,286 after the penalty on NH, FL and SC. Out of those 2,286 delegates Santorum and Gingrich are not elegiable for some 500 or so. Santorum and Gingrich each didn't make it on several ballots. Some of the states one did while the other didn't and vise versa.
Which leaves them with only being able to get delegates from a pool of 1,722. Then if you subtract any delegates that Ron Paul and Romney already have the number is lower. On top of this 503 delegates are considered unbound, meaning they can vote for whoever they want.
Edit: Basically if either Gingrich or Santorum stay in this race, it guarntees a brokered convention.
I think the reason they are staying in is to stop Ron Paul and the movement. Face it, if it was just Ron and Mittens, Ron would be getting ALOT more attention and his Liberty message would be converting alot more people. They are diluting our impact by staying in. Right now the media is busy spinning the other 3 but if it was just Paul and Mittens the media would not be able to continue the blatent bias against Paul and we would be picking up alot more delegates as gaining momentum quickly. This is Ron Pauls strategy of sticking in there till there are only 2 standing and the GOP establishiment is doing everything they can to derail us before we get there. So we need to buckel down, stop being pessimistic, and realise...WEVE ONLY JUST BEGUN!!!!
So that means Gingrinch and Santorum need to get approximately 66.4% of all delegates they qualify for. Us Ron Paul supporters have been accused of being overly optomistic but The Grinch and Santorum are now in the realm of just being flat out DELUSIONAL.
EDIT: We should start a meme of The Grinch and Santorum are the 66%'s in this election or something like that.