From what I have read tonight it sounds like Rick and Newt have decided that they both need to stay in and take it all the way to the convention where all bets are off. If one of them drops out it would make it much easier for Romney to gain 50% of the delegates. They both need to stay and and each needs to do reasonably well to keep the democrats from having candidates on both sides. If Romney is the nominee it’s a democrat win-win. At this point I would be relatively happy with Rick or Newt as opposed to Romney..gags.
The agreement also allows for conservation of their limited resources. Gingrich can focus on those states where he has an advantage (e.g., the South), Santorum can focus on those states where he has an advantage (e.g., the Midwest).
Romney gets whipsawed, always having to confront the stronger of the two.