PRINCETON, NJ -- Republicans and Republican-leaning independents have no clear favorite for the party's 2012 presidential nominee at this point, with Mike Huckabee (18%), Mitt Romney (16%), and Sarah Palin (16%) in a statistical tie for the lead. They are the only candidates in the crowded field of potential candidates who register double-digit support. Minnesota Congresswoman Michele Bachmann, and former Utah Gov. and current Ambassador to China Jon Huntsman were included for the first time and received 4% and 1%, respectively.

New Jersey Gov. Chris Christie, who maintains he does not plan to run for president, is still volunteered by 1% of respondents, as is Indiana Congressman Mike Pence. Pence's name was included as an explicit option in previous Gallup surveys but he recently announced he would not be a candidate for president in 2012. South Dakota Sen. John Thune, who announced on Tuesday he would not enter the race, also gets 1% of the vote.

The results are based on interviews conducted Feb. 18-20, with 1,326 Republicans and Republican-leaning independents on the Gallup Daily survey. Gallup had previously asked Republicans for their 2012 nomination preferences in November and September.

Those earlier polls also showed a top tier consisting of Romney, Palin, and Huckabee, though Huckabee trailed Romney (by a statistically significant margin) and Palin in the September poll. Huckabee's support has increased in each of the subsequent updates, and his total six-point gain since September is the largest for any of the candidates to date.

Most of the other candidates are now within one or two percentage points of their September and November estimates. Two exceptions are Romney, whose current 16% is a bit lower (though still within the margin of error) than his 19% readings last year, and Newt Gingrich, whose current 9% of the vote is down from 13% in November but the same as September.

As is usually the case in early nomination polls, the top candidates tend to be the best known. Huckabee, Romney, and Ron Paul all sought the 2008 Republican presidential nomination, Palin was the party's vice presidential nominee that year, and Gingrich was the speaker of the House from 1995-1999. So far, none of the lesser-known candidates, including some current and former state governors, has broken out of the low single digits.

There aren't wide differences among the top competitors among different subgroups of Republicans, though Huckabee fares slightly better among core Republican identifiers than among Republican-leaning independents, among conservatives than among liberals or moderates, and among frequent than among less frequent churchgoers, and among Southerners.

Palin has greater appeal to college nongraduates than college graduates and to lower- and middle-income Republicans than upper-income Republicans. To date, there is not a pronounced gender gap in Palin's support.

Older Republicans are significantly more likely than younger Republicans to support Romney.

Preferences for the leading candidates are generally similar among Tea Party supporters and nonsupporters.

Implications

Gallup's polling on Republicans' preferences for their party's 2012 presidential nominee clearly underscores that there is no early front-runner. This is a departure from what Gallup has found for the GOP nomination since 1972, when state primaries became the main way of selecting the nominee. Previously, a particular candidate held a strong lead at the outset of the Gallup's Republican nomination polling, and that candidate usually led for most of the nominating campaign and eventually won the nomination. The only exception to that general pattern was in 2008. Rudy Giuliani led in early preference polls that year, but his lead began to dwindle in late 2007 and he performed poorly in the initial primaries and caucuses. The current wide-open nature of the 2012 GOP race to date suggests a competitive and perhaps dynamic race ahead.

Although many of the potential 2012 candidates have campaigned in key early primary and caucus states, the most prominent ones have yet to officially declare their candidacies. The field should begin to take shape in the coming months leading up to the first candidate debates this spring.