The narrowing GOP presidential field

As Republicans officially jump into - or opt out of - the 2012 presidential race, here's an up-to-date accounting of who's in, and who might still launch a campaign in the weeks and months to come.

MITT ROMNEY

Mitt Romney, the former Massachusetts governor and unsuccessful 2008 candidate, has a lot going for him in his 2012 presidential run: He has worked hard to establish his conservative credentials following his relatively moderate tenure as Massachusetts governor, and is currently leading in several GOP presidential polls. His recent performance in the first major GOP presidential debate seemed to solidify his status as the unofficial GOP frontrunner. Still, Romney has liabilities: His Mormon faith remains a potential roadblock to some voters, and some see him as a political opportunist. Plus, the health care bill he signed into law in Massachusetts is already proving to be a problem among Republican primary voters -- especially since it looks eerily familiar to the national law President Obama passed in 2010.

MICHELE BACHMANN

Minn. Rep. Michelle Bachmann proved her strength as a possible contender in CNN's Republican presidential debate. The Tea Party darling captured the audience's attention during the debate, and she stood out among the field of otherwise male - and often stiff - candidates. She's also a prolific fundraiser, and is able to use the Tea Party label to her financial advantage. However, she can be a controversial figure: Bachmann's rhetoric and aggressive posture have earned comparisons to the most divisive aspects of Sarah Palin

RICK PERRY

Texas governor Rick Perry is starting to make moves toward a run, despite past statements that he has "no intention" of doing so. But the charismatic fiscal conservative is a strong fundraiser, and is expected to immediately jump to the top tier of candidates. However, Perry could face some criticism for having suggested in the not-so-distant past that Texas could secede from the union.

NEWT GINGRICH

Newt Gingrich's presidential campaign has faced a number of setbacks in recent weeks. First, he criticized Paul Ryan's budget plan as being right-wing social engineering. (He later walked back the comments, which had drawn ire from the right.) Then, he came under some fire for reports noting that he had at one point racked up in the neighborhood of $500,000 debt at Tiffany & Co. And finally, in what some characterized as a "potential death knell" for his White House bid, Gingrich's top aides resigned en masse from his presidential campaign in June. Still, the former House speaker has said he will continue to fight for the nomination.

RON PAUL

The Texas Republican and longtime congressman has a loyal following due to his staunch libertarian views - and is making his third run for the presidency this year. Still, Paul has so far failed to gain the broad audience needed to win a presidential nomination. And while his brand of conservatism may have been singular in years past, the Tea Party movement grew without him as its leader and he now faces better-known Republican opponents who espouse many similar ideals.

HERMAN CAIN

Herman Cain, Former Godfather's Pizza CEO and a relative political newcomer, wowed in the first official GOP debate in May - particularly in light of his relative lack of name recognition. But in subsequent events with more prominent candidates, he has failed to gain the same recognition. Whether or not he has the support and political savvy to stay in the game remains to be seen.

RICK SANTORUM

Former Pennsylvania Senator Rick Santorum also has strong conservative credentials - his social stances play well among Iowa voters and his conservative fiscal views will help with Tea Partiers - but he is not nearly as well-known as a number of the other candidates. His lackluster performances in the recent GOP debates has done little to enhance his profile, and he may be too conservative to earn support for moderate voters in New Hampshire, Florida and other key states.

SARAH PALIN

Speculation over whether or not former Vice Presidential nominee Sarah Palin will run for president has long been building, and recent signs suggest she's seriously considering a bid: the former Alaska governor recently announced an East Coast bus tour; authorized a feature-length film about her rise; has added staff to her team, and said she has "that fire in the belly" for a run. But the verdict is out on whether or not her unconventional campaign strategy (if that is indeed what it is) is being effective. In a recent CBS News poll of the Republican field, most Republicans said they don't want Palin to run for president. Still, a Palin entrance in the race would certainly change the game.

JON HUNTSMAN

The former Utah governor will officially announce his candidacy in late June, but he has been laying the groundwork for a possible candidacy for several months: earlier this year, he resigned his ambassadorship to China in order to consider a bid. Huntsman has the top foreign policy chops of anyone in the GOP field, and he has strong business credentials. But as a former employee of President Obama, the relative moderate may struggle to break away from the pack in the GOP field.

RUDY GIULIANI

Former NYC mayor Rudy Giuliani is said to be "very close" to jumping in to the race for the GOP presidential nomination. Giuliani, who became known as "America's mayor" for his response to the Sept. 11 terrorist attacks, launched a failed presidential bid in 2008, but he could benefit from his substantial name recognition were he to throw his hat into the ring.

GARY JOHNSON

Former New Mexico Governor Gary Johnson announced his presidential bid in April, but since then he's flown relatively under the radar: a June poll showed him polling at around 2 percent support. Johnson, a staunch libertarian, is an anti-interventionist when it comes to foreign policy, and vocally supports gay rights. Still, while his position on those issues set him apart from most other GOP candidates, Johnson holds up his record as governor of New Mexico as proof of his small-government, fiscal conservative credentials.

CHRIS CHRISTIE

New Jersey Gov. Chris Christie has fervently - and repeatedly - emphasized that he is not going to run for president in 2012. Nevertheless, that hasn't stopped GOP leadership from trying to change his mind: in May, citing dissatisfaction with the current field of Republicans, a handful of influential Iowa donors apparently attempted to recruit him for the race.

THADDEUS McCOTTER

Five-term Michigan congressman Thaddeus McCotter jumped into the presidential race in early July, making him the third sitting House member to do so. The congressman, who is little-known on a national level, faces a number of challenges in what looks like an uphill bid for the nomination: Not only will he have to make his name known in a crowded field; he'll also have to make up serious ground fundraising wise. (According to an adviser on his campaign, he will start out the race with a campaign chest in the mid-six figures.) Nevertheless, with his conservative credentials and Midwestern background, the candidate could pick up some support in the crucial Iowa primary.