Republican presidential candidate Donald Trump might be getting more and more support from American voters nationwide as the nominations draw nearer, but he is not getting much love from pastors, whose support he has long aspired for.

A recent survey conducted in mid-January by a Nashville-based Christian research organisation showed that the controversial businessman only had 5 percent support from Protestant pastors, ranking only as the religious leaders' fourth choice among Republican presidential hopefuls.

Forty-eight of the 1,000 Protestant pastors surveyed, most of whom identified themselves as Republicans, said they were still "undecided" on their choice for president.

In an interview with CBN News, LifeWay Research executive director Ed Stetzer said some Protestant pastors may still have not picked yet who they will vote for president because they are busy with their work. "Plus, they're not in Iowa so they don't have to decide yet," Stetzer said.

He said Trump's low support among pastors despite his high popularity among the general public shows "a huge gap between the pulpit and the pew."

Among those who have already picked their presidential candidate, 29 percent said they would vote for Texas Senator Ted Cruz.

Retired neurosurgeon Ben Carson, who identified himself as a Seventh-Day Adventist, came in second place among Republican pastors, garnering 10 percent of their support.

In third place was Florida Senator Marco Rubio, a Catholic, who got 8 percent support from Republican pastors.

Only 2 percent of these religious leaders said they will vote for former Gov. Jeb Bush, John Kasich, and Gov. Chris Christie.

In a related news, Trump said he will continue to support abortion restrictions if he wins as president, but with certain exceptions.

"Let me be clear — I am pro-life," Trump wrote in an opinion article published on The Washington Examiner on Saturday. "I support that position with exceptions allowed for rape, incest or the life of the mother being at risk."