A new national poll of Republican primary voters indicates thatBen Carson has taken a small lead in the race for the party’spresidential nomination, knocking Donald Trump from a position hehas held for months.

Twenty-six percent of likely voters say Carson istheir top pick for the nomination, four points ahead of Trump at 22percent. The poll, conducted by CBS and The New YorkTimes, has shown Trump on top ever since it began surveying voterslast July. Out of more than 30 polls tracked on the website RealClearPolitics, this is onlythe second since early July that doesn’t have Trump in thetop spot. The news comes on the heels of a poll giving Carson a big14-point lead in Iowa, whose caucuses kick off the primary season.(RELATED: New Iowa Poll Shows Carson WithDouble-Digit Lead)

No other Republicans are in double digits in the new poll. MarcoRubio is third with 8 percent support, followed by Jeb Bush andCarly Fiorina with 7 percent apiece. Every other candidate isclustered at 4 percent or less.

Carson’s rise is based on picking up more support fromjust about all groups, but his core base still shows substantialdifferences with Trump’s. Carson has amassed tremendoussupport among evangelical voters, who support him over Trump bymore than 20 percentage points. Carson is also more popular withwomen than men, and attracts more conservatives, while Trumpappeals more to moderates and those without a college degree.

Carson’s lead could be quite unstable, though. Only 19percent of his supports say they are firmly committed to backinghim, while more than half of Trump’s supporters say the same,meaning the business mogul likely has a firmer base on which torely.

The poll was conducted from Oct. 21-25 and had a sample size of575 Republican primary voters. The margin of error was plus orminus 6 percentage points.

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