If this were a normal election year we'd expect some of the "final four" to drop out after tomorrow's contests. As anybody who's been following the process knows, 2012 is not a normal election year.
Romney, with the most delegates, cannot be expected to drop out. Paul's goal seems to be to give voice to the views of the libertarian subset of the GOP and he is certainly accomplishing that. Paul doesn't seem to care much about winning states, or even the nomination, so he won't drop out.
That leaves Gingrich and Santorum, struggling to become the one true voice of very conservative voters. It is clearly in Romney's interest for both of them to continue in the race, dividing the anti-Romney vote between them.
