Beyond the widely reported four-way tie between Herman Cain, Ron Paul, Mitt Romney and Newt Gingrich in the first Republican presidential contest of 2012, a new Bloomberg News survey shows Ron Paul with comparatively few flaws in the eyes of likely Iowa caucus participants. The other top contenders, by contrast, all face serious policy and personal obstacles to winning supporters. Here’s a rundown of the challenges confronting each of the top candidates.

Romney: Almost six in 10 likely caucus participants (58 percent) say they would rule out voting for a candidate who backed a health insurance mandate, one of the key provisions in the federal health reform law passed last year. Mitt Romney signed a mandate into law as governor of Massachusetts, but has had to defend himself against criticisms that “Obamacare” was modeled after “Romneycare.”

Gingrich also supported a mandate in the past.

Gingrich: Nearly half (48 percent) say they’ll disqualify a candidate who has “been married three times and had extramarital affairs” (Gingrich is the only candidate who fits this description).

Cain: A smaller percentage of likely caucus-goers (30 percent) say they’ll rule out a candidate accused of sexual harassment (if you’ve been living under a rock, that’s Herman Cain). Cain’s numbers in national polls have soured in the weeks since the scandal broke, even as most Republicans say it won’t make a difference in their vote. In Iowa, about three in 10 of Republicans say they believe Cain’s story that he never behaved inappropriately, while nearly as many are dubious or skeptical. More than a third of voters say they’ve yet to make up their mind.

A bigger problem for Cain may be waning enthusiasm and a muddled message. Cain posted his worst “positive intensity score” among Republicans and GOP-leaning independents in Gallup polls since April, a measure that shows his strong opponents now rival his strong supporters. And the top one-word reactions to Cain in an October Post-Pew poll were “999,” “business,” “interesting,” and “good,” (OK, next up was “pizza”). After almost three weeks of intense scrutiny over sexual harassment allegations, it’s an open question how much of Cain’s initial message still resonates.

Paul’s biggest obstacle to an Iowa victory, by contrast, was that he couldn’t seem to grow his support beyond a highly intense cadre of loyalists. He’s clearly broken that threshold in the new Iowa poll. His other apparent weaknesses – an isolationist approach to foreign policy and opposition to ethanol subsidies – may matter less to an electorate focused deeply on the economy. Fewer than three in 10 Iowa voters say they would rule out a candidate who wants to end ethanol subsidies, an action Paul endorses.

In addition to his fast rise from 12 percent in October, Paul is leading other top candidates in reaching out to voters. Fully two thirds of likely caucus participants have been contacted by the Paul campaign, compared with fewer than half that have heard from the Cain, Romney or Gingrich campaigns.

Have another take on Paul’s electability? The comments section awaits!

Other top polls...

Repeal health reform? By 47 to 42 percent, Americans would rather repeal the health care overhaul law passed last year than keep it in place, according to a Gallup poll released Wednesday. Republicans favor repealing the law by an 8-to-1 margin, while Democrats favor keeping reforms by a smaller 3-to-1 margin. Independents split 48 to 43 percent in favor of repealing the law.

An October Kaiser Family Foundation poll found just 34 percent of Americans with a favorable view of the new law, the lowest in monthly polls since it was signed by President Obama. A slight majority, 51 percent, saw the law negatively.

Americans (still) doubtful of supercommittee success – Almost eight in 10 Americans are doubtful the congressional “supercommittee” will agree on a deficit reduction plan by its Nov. 23 deadline, according to a CNN poll released Wednesday. A similar 75 percent of the public doubted Republicans and Democrats would agree on a deficit reduction plan in an early October Post-ABC poll.

As the Post’s Chris Cillizza pointed out, “the American public is either: a) entirely uninterested/unaware of the debt machinations in D.C. or b) deeply pessimistic that Congress can/will get anything done.” Fully half the public said they were “not at all familiar” with the supercommittee’s work in a Politico/George Washington University poll (pdf) released Monday.

Why use social media? More than six in 10 social networking users say staying in touch with friends and family are major reasons they use Web sites like Facebook and Myspace, according to a survey by the Pew Internet project released Tuesday. Connecting with long-lost friends is a major factor for half of users, but fewer than one in 10 say finding new friends is a key motivator for using networking sites. Still fewer – just 3 percent – say finding love (or dating partners) is a big reason they use social media.

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