"...all section 501(c)(3) organizations are absolutely prohibited from directly or indirectly participating in, or intervening in, any political campaign on behalf of (or in opposition to) any candidate for elective public office."

Wayne Slater of the The Dallas Morning News is on the case:

AUSTIN - The Texas Restoration Project, aimed at motivating pastors to influence state elections, has become a national model to boost evangelical influence in the presidential race.

Mike Huckabee hopes to be the beneficiary, meeting privately next week with Christian pastors in Florida after similar briefings in Iowa and South Carolina.

In Texas, the project held a series of closed-door pastor briefings, urging ministers to encourage their congregations to register and vote for candidates who match their moral agenda.

Bankrolled largely by wealthy Republican political contributors, the effort recruited 300,000 "values voters" in Texas and helped re-elect Gov. Rick Perry and pass a constitutional amendment to ban gay marriage.

The Texas Restoration Project (unsuccessfully)  sought to fly beneath the radar of press to rally pastors in Florida -- apparently for the benefit of Huckabee -- who was the only candidate to attend a major rally in Orlando. The rally featured  the ubiquitous David Barton, who spends much of each election year on the road barnstorming for Religious Right Republicans.  

Slater
reported:

Mike Huckabee took the stage Monday night before hundreds of Florida pastors and sought to distinguish himself from his Republican rivals on the issue of abortion. It was a private affair, no press invited. The public was barred. The stop wasn't even on Huckabee's official schedule.

Huckabee was the keynote speaker at an Orlando hotel at a two-day gathering called the Florida Renewal Project, modeled on the Texas Restoration Project, aimed at getting pastors involved in influencing elections.

Florida Renewal Project sponsors tried to keep the gathering out of the public eye... Huckabee was introduced by end-times novelist Tim LaHaye, who called him "a man of conviction, a soul winner."

Other prominent speakers included Mathew Staver, the dean of Liberty UniversityLaw Schol (founded by Jerry Falwell); Don Wildmon, honcho of the American Family Association; and former U.S. Rep. Bob McEwen of Ohio -- all of whom have endorsed Huckabee. Also speaking was prominent (and apocalypticly minded) Christian Zionist, John Hagee (who has apparently not made an official endosement):  

San Antonio televangelist John Hagee also is a featured speaker. Mr. Hagee invited Mr. Huckabee to speak at his megachurch earlier this month and accompanied him to a fundraiser at the home of Mr. Leininger, the Texas Restoration Project financial backer.

But the stealth campaign for Huckabee -- appears to be ongoing.