Although he remains as the Republican presidential frontrunner, business mogul Donald Trump is not a favourite among highly religious Republicans, ranking just 12th among Republican presidential contenders, according to a new poll.

A Gallup poll conducted from Aug. 1 to Sept. 8 on Republican candidates based on religiosity showed that Trump got a net satisfaction rating of 22 percent, compared to Ben Carson who topped it with 56 percent.

Gallup's editor-in-chief, Frank Newport, said the results are in contrast to the perception that Trump enjoys the full support of evangelical Republicans.

"These assumptions about Trump's level of support among evangelicals appear to be based on trial heat polls wherein Republicans are forced to choose one and only one candidate for whom they would, in theory, vote," he wrote.

The poll includes a standard measure of "highly religious," which is "based on self-reports of religious service attendance and importance of religion in their daily lives."

"The results show that Trump does not, in fact, receive high levels of support from highly religious Republicans. His net favourable rating is 12th in the list of 17 GOP candidates among highly religious Republicans. Ben Carson is the clear leader among the highly religious group," Newport said.

Following Carson are Mike Huckabee and Marco Rubio with 49 percent each; Ted Cruz, 45 percent; Scott Walker, 43 percent; Carly Fiorina, 36 percent; Rick Perry, 32 percent; Bobby Jindal, 29 percent; Jeb Bush, 25 percent; Rick Santorum, 25 percent; John Kasich, 22 percent; Trump, 22 percent; and Rand Paul, 12 percent.

"As noted, Trump's net favourable rating among the highly religious group is well below average for these candidates, at 22 percentage points, tying him with John Kasich. Trump is one of the few candidates who does better among the moderately religious, and he does only slightly worse among those who are not religious," Newport said.

He said Carson's net favourable rating among the highly religious is over two and a half times higher than Trump's.

"In fact, four candidates in all—Carson, Mike Huckabee, Marco Rubio and Ted Cruz—have more than double the net favourable rating among highly religious Republicans that Trump does," he added.

He concluded that, "Bottom line: There is no sign in these image data that Trump has any exceptional positioning among highly religious Republicans."

Carson catching up with Trump in New Hampshire

In another poll, Carson has gained support in New Hampshire, placing second to Trump, according to CNN based on a Monmouth University poll.

While Trump still leads in the poll with 28 percent, Carson climbed 12 percentage points to 17 percent since July.

Kasich placed third with 11 percent followed by Cruz, Fiorina and Bush.

"Carson's rise—fueled by a 73 percent favourability rating, compared to just 10 percent who say they view him unfavourably—comes even though New Hampshire lacks the base of evangelical Christians who support Carson in Iowa and South Carolina, two other important early-voting states," the CNN report noted.