Herman Cain's momentum in the Republican presidential primary appears to be no fluke.
A new CBS News poll finds the former Godfather's Pizza chief tied with Mitt Romney for first place among likely Republican primary voters, with 17 percent support apiece. That's a 12-point jump for Cain, who was at 5 percent in the same poll just two weeks ago. The poll's margin of error among likely Republican voters is 6 points.
But with Cain's prospects on the rise, Rick Perry's stock has plummeted. The CBS poll finds Perry in third place with 12 percent support, an 11-point drop in two weeks.
The other candidates are stuck in single digits, including Newt Gingrich (8 percent); Ron Paul (7 percent); Michele Bachmann (4 percent); Rick Santorum (3 percent) and Jon Huntsman (2 percent).
Cain's sudden jump in the polls reflects greater enthusiasm for him among the GOP's most conservative voters. The CBS poll finds the former radio host leading Romney among self-described conservatives—there he clocks 31 percent support, compared to Romney's 15 percent. Cain also leads among Republicans who describe themselves as supporters of the tea party, with 24 percent support. Romney is that group's second choice, with 17 percent support, followed by Gingrich (13 percent) and Perry (12 percent).
Still, the race remains incredibly fluid. According to the CBS poll, 18 percent of likely GOP voters remain undecided in the race, while a whopping 76 percent say it's still "too soon" to make a final decision on which candidate they will support for the nomination.
One good sign for Romney: Thirty-two percent of likely voters view the former Massachusetts governor as the candidate with the best chance of beating President Obama next year. By comparison, 21 percent view Perry as most electable. Cain trails at just 8 percent. The margin of error among likely voters is 3 points.
The CBS poll comes on the heels of a trio of state surveys released by Public Policy Polling on Tuesday that found Cain leading GOP primary contests in North Carolina, Nebraska and West Virginia. An ABC/Washington Post poll released earlier this week found Cain tied for second place with Perry nationally.
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