I think if Newt drops out a significant number of his voters goes to Romney, and be an overall loss for conservatives.
This is what the “voter's second choice” polls cited by CharlesWayneCT were showing in January... a significant percentage of Gingrich voters had Romney as their second choice, and the same for Santorum voters.
We really, really, really need to get current poll data on Santorum and Gingrich voters’ second choices, preferably broken down state-by-state in the upcoming primary and caucus states.
I'm pinging this to the people who seem to be the key Santorum and Gingrich supporters here. I would be extremely unhappy if a pullout by either Gingrich or Santorum had the effect of boosting Romney.
My goal is to defeat Romney in the primary and Obama in the general election. I like Santorum, but I can live with Gingrich. If the best way to defeat Romney is for both candidates to stay in the race and combine their votes at the convention, that's fine with me.
Time is quickly running out and we do not have room for mistakes.