Ben Carson now has a 14-point lead over Donald Trump among likely GOP caucus-goers in Iowa, according to a Monmouth University poll released Monday.
Thirty-two percent said they back Carson compared to 18 percent for Trump.
The new poll also found 10 percent said they support Sen. Ted Cruz, R-Texas, 10 percent said they back Sen. Marco Rubio, R-Florida and 8 percent said they back former Florida Gov. Jeb Bush. Five percent said they back former Hewlett Packard CEO Carly Fiorina, three percent support Sen. Rand Paul, R-Kentucky, two percent back former Arkansas Gov. Mike Huckabee, two percent support Louisiana Gov. Bobby Jindal and two percent support Ohio Gov. John Kasich.
None of the other five candidates received one percent or more of support.
Carson, a retired neurosurgeon, now leads Trump among all ideological groups. He leads Trump by nine percentage points among very conservative voters and by 21 percentage points among somewhat conservative voters. Carson also has a 17-percentage-point lead over Trump among moderate to liberal voters in Iowa.
More than a third of likely GOP caucus-goers who are evangelical Christians back Carson while 18 percent of that group said they support Trump. Carson also holds a 9-percentage-point lead over Trump among non-evangelicals.
Carson leads Trump among women 34 percent to 17 percent, the poll found, and Carson leads Trump among men by 11 percentage points.
Eighty-four percent said they view Carson favorably and 53 percent said the same about Trump.
Despite Carson's double-digit lead, only 19 percent of GOP caucus-goers said they have made a final decision about which candidate to support at the caucuses in February.
A CBS News Battleground Tracker survey released over the weekend found Trump and Carson are tied at 27 percent in Iowa.
Polls from last week, however, found that Carson had taken the lead among Republican voters in Iowa.
The poll surveyed 400 Iowa voters between October 22 and October 25 with a margin of error of +/- 4.9 percentage points.