Have a series of tough challenges to his 9-9-9 plan and a couple of stumbles on the campaign trail slowed down Herman Cain?  According to a sneak peek at the new New York Times/CBS poll at The Caucus, the answer is clearly no:

Herman Cain, the former restaurant executive, is riding a wave of support among Republican primary voters that has placed him in a statistical dead heat with rival Mitt Romney, the former Massachusetts governor, in a race that has been characterized by momentum swings among the candidates.

The poll found Mr. Cain with the highest level of support, with 25 percent of Republican primary voters, and Mr. Romney with 21 percent. This difference is within the poll’s margin of sampling error.

Adding to the fluidity of the contest, about one in 10 Republican primary voters say they would like to see someone else nominated.

Support for Rick Perry, the governor of Texas, has weakened to 6 percent, placing him among the second-tier candidates with Newt Gingrich and Ron Paul, who have the backing of 10 percent and 8 percent of Republican primary voters, respectively. Michele Bachmann, Jon M. Huntsman Jr., andRick Santorum are all struggling to gain traction with the Republican electorate – none of the three drew more than 2 percent of support among Republican primary voters.

I’m not sure that the 10% who want another candidate “add[s] to the fluidity” of anything.  We’ve passed at least one or two deadlines for entry at this point, and we’re rapidly approaching a couple more.  No one will have the organization or the funding to jump into this race now and perform credibly.  Besides, 10% isn’t exactly a groundswell for change; it equals Newt Gingrich’s support and surpasses most of the other candidates, but almost half of all respondents choose either Cain or Romney.  Add in Gingrich and you get more than a majority.

The survey took place before Perry’s big unveiling of his economic plan, but it’s also clear that he needs it to be a game-changer.  Falling into the statistical soup with the rest of the second tier this late in the game is a big hole from which to climb out, but Perry has enough money to guarantee himself some coverage.  He needed the policy heft that a detailed economic plan will give him, but a lot depends on those details, more of which will come out today after a briefing for new media that will take place this morning.

The big story is the durability of Cain, at least thus far.  He’s running one of the most unconventional campaigns in recent memory — or at least one of the more successful unconventional campaigns.  As I said yesterday, Cain is drawing from a deep well of goodwill among Republican voters who love his biography and his sunny, no-nonsense approach to politics.  Voters can relate to Cain, and unless he seriously collapses, he’s not likely to lose that affection.