Huckabee finished as a surprise runner-up to Sen. John McCain (R-Ariz.) in the 2008 contest for the Republican presidential nomination after emerging from relative anonymity to win the Iowa caucuses that year. Since then, he has remained immensely popular with the Republican base, consistently ranking at or near the top of presidential primary polls. He has been viewed more skeptically by the members of the Republican Party establishment, whom Huckabee has labeled "elitist."
Huckabee began working for Fox News as a commentator in June 2008, several months after conceding the GOP primary to McCain. Huckabee contributed to the network's general election coverage that fall, and also signed a contract to host the "Huckabee" program, which premiered that September. There were conflicting reports in recent weeks over whether or not Fox News had issued an end-of-May deadline for Huckabee to announce his presidential decision.
The most obvious beneficiaries of Huckabee's departure from the race: former Minnesota Gov. Tim Pawlenty (R) and Rep. Michele Bachmann (R-Minn.). Both have made overt appeals to the evangelical community and are actively courting Tea Party activists. It's also a boon for long shots like businessman Herman Cain (R) and former Sen. Rick Santorum (R-Pa.), a staunch social conservative whose hopes of competing in Iowa would have been severely diminished had Huckabee entered the race.
-- Updated at 9:50 p.m.