According to Elephant Watcher:
"Jon Huntsman announced today that he was dropping out of the race. He also immediately endorsed Mitt Romney. The Campaign Status page has been updated to reflect Huntsman's departure; there are now only five candidates remaining. Huntsman needed a win in New Hampshire to really propel his campaign forward, and he came nowhere close. However, he remained in the race for a few additional days as a way of showing appreciation to the 17% of New Hampshirites who voted for him.
Huntsman's departure will have little impact on the race. For some time now, he has had a 0% chance of winning the nomination, and he has been polling at near zero in the remaining states. Huntsman's endorsement of Romney does add a small amount to the impression that Romney is inevitable. Of the candidates that have either dropped out or decided not to run, those who have decided to endorse (e.g. Christie, Huntsman, Pawlenty) have all endorsed Romney. Huntsman no longer being in the ra