In addition to leading the GOP field, Carson also becomes the first GOP candidate in the NBC/WSJ poll to get majority support as either a first or second choice among GOP primary voters.
A combined 50 percent of Republican voters pick Carson as either their first or second choice in the GOP presidential race — followed by 35 percent for Trump, 24 percent for Rubio and 23 percent for Cruz.
Carson "has broad support, but we don't know yet the depth and commitment of that support," Yang says.
"It doesn't mean it is enduring," but it's still noteworthy that a majority of Republicans pick Carson as either their first or second choice, adds GOP pollster McInturff.
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And while there's still plenty of time for an establishment GOP candidate to beat Carson or Trump, Democratic pollster Peter Hart wonders if the 2016 Republican race is shaping up to resemble 1964, when Barry Goldwater won the GOP nomination.
"What if the cake is baked?" Hart asks. "This is not a status-quo electorate."
This NBC/WSJ poll was conducted (by telephone and cell phone) Oct 25-29 of 400 GOP primary voters, and it has a margin of error of plus-minus 4.9 percentage points.