Herman Cain is still on top in Iowa, but a majority of registered voters in the Hawkeye State remain deeply ambiguous about who they will support in the first-in-the-nation caucuses less than two months from now. That's the finding of a new Iowa State University/(Cedar Rapids) Gazette/KCRG poll of 1,256 registered Iowa voters in the topsy-turvy GOP presidential nomination contest. Once again, Cain seems little affected by the sexual harassment allegations swirling around him, leading Republican presidential candidates with 24.5 percent support among likely participants in the Jan. 3 caucuses. Ron Paul follows with 20.4 percent, and Mitt Romney ranks third at 16.3 percent. Next comes "Can't Decide," at 8.1 percent, followed by the rest of the single-digits GOP field: Rick Perry, at 7.9 percent; Michele Bachmann at 7.6; Newt Gingrich at 4.8.; Rick Santorum at 4.7; and Jon Huntsman at 0.0 (ouch). (On the other hand, the latest Rasmussen Reports national telephone survey of likely Iowa Republican caucus-goers shows Gingrich with 32 percent, followed by Romney at 19 percent. Cain, who led in Iowa last month, drops to third with 13 percent of the vote. Paul draws 10 percent, and Perry and Bachmann each grab six percent). Those are the hard numbers. But the Iowa State pollsters suggest the race remains fluid: "Respondents were asked how certain they were of their choice and the majority of them (52.3 percent) indicated that they were undecided. Another 30.1 percent answered that they were only leaning toward one candidate. Only 16.5 percent indicated that they had definitely decided whom they would support." For Bachmann, the Minnesota Republican in the field, the poll suggests both good and bad tidings. On the plus side, a lot could change. On the downside, Iowa seems impervious this year to the kind of retail politicking that is the state's calling card and Bachmann's specialty. Two of the leaders, Cain and Romney, have barely gotten their toes wet in Iowa. Meanwhile, candidates like Bachmann and Santorum, who have all but applied for drivers' licenses in the state, are trailing badly.