Rick Santorum won the endorsement Tuesday of two leading Iowa religious conservatives, boosting his efforts to unite the state's evangelical voters behind his candidacy in the Jan. 3 caucuses that begin the Republican presidential nominating contest.

Bob Vander Plaats, president of the Family Leader network of pastors and activists, and Chuck Hurley, president of the Iowa Family Policy Center, said that social conservatives' divided loyalties risk handing a victory to an unacceptably moderate front-runner.

Yet they were personal endorsements. The Family Leader group itself declined to back any candidate after its board could not agree on a choice, although it reached consensus that former Massachusetts Gov. Mitt Romney and Texas Rep. Ron Paul were unacceptable.

"I believe Rick Santorum comes from us," Vander Plaats said at a news conference in Urbandale, Iowa. "Not to us. He comes from us. He is one of us."

Santorum, a former two-term senator from Pennsylvania, is a staunch foe of abortion rights and same-sex marriage who argues that the nation's economic problems stem from the breakdown of the family. He has lagged in polls but has campaigned in Iowa more than any other candidate and has built grassroots support, according to state strategists.

Hurley said that Santorum "meets and exceeds the biblical qualifications" to earn the support of Iowa evangelicals.

The developments were a blow to former House Speaker Newt Gingrich, who had been seeking support from social conservatives in an effort to cement his status as the leading alternative to Romney. Vander Plaats had sent early signals that he favored Gingrich, but Iowa GOP sources said that activists pushed back, concerned about Gingrich's three marriages and admitted infidelities.

Gingrich was a major funder of the successful effort to recall three Iowa Supreme Court justices last year after the court ruled a ban on same-sex marriage was unconstitutional, a campaign that Vander Plaats led. Santorum was also an ally in that effort, traveling the state extensively to urge the ouster of the justices.

In 2008, six of every 10 voters who participated in Iowa's Republican contest said they were evangelical or born-again Christians, according to exit polls, and they delivered a surprise victory to former Arkansas Gov. Mike Huckabee, a Baptist minister.

"We're the candidate right now that has the momentum, that has the message that's resonating to the people of Iowa," Santorum told reporters after a campaign stop in Pella, Iowa. "I think they're probably catching that and see this as the campaign that's going to be the conservative alternative."

Vander Plaats said he hoped that Rep. Michele Bachmann and Texas Gov. Rick Perry, who each also enjoy backing from Christian conservatives, would drop out of the race and throw their support to Santorum. In the aggregate, the three candidates have a strong plurality of the Iowa vote, Vander Plaats said.

"You put those numbers together, and you have a dynamo candidate coming out of Iowa," he said. "Our fear all along is the conservatives could fracture their vote."

Contact politics writer Thomas Fitzgerald at 215-854-2718, tfitzgerald@phillynews.com, or @tomfitzgerald on Twitter. Follow his blog, "The Big Tent," at www.philly.com/BigTent