PRINCETON, NJ -- Shortly after announcing his official candidacy, Texas Gov. Rick Perry has emerged as rank-and-file Republicans' current favorite for their party's 2012 presidential nomination. Twenty-nine percent of Republicans and Republican-leaning independents nationwide say they are most likely to support Perry, with Mitt Romney next, at 17%.

These results are based on an Aug. 17-21 Gallup poll, the first conducted after several important events in the Republican nomination campaign, including the second candidate debate, the Iowa Straw Poll, and Perry's official entry into the race after months of speculation.

Romney and Perry essentially tied for the lead in late July, based on re-computed preferences that include the current field of announced candidates. Gallup's official July report, based on the announced field at the time and thus excluding Perry, showed Romney with a 27% to 18% lead over Michele Bachmann. Romney enjoyed an even wider, 17-percentage-point lead in June over Herman Cain among the field of announced candidates (Gallup did not include Perry among the nominee choices before July).

Perry's official announcement may have overshadowed the Aug. 13 Iowa Straw Poll, which Bachmann won narrowly over Ron Paul. Neither candidate appears to have gotten a big boost from the straw poll results; Paul's support was up slightly from July and Bachmann's down slightly.

Perry is a strong contender among key Republican subgroups. Older Republicans and those living in the South show especially strong support for him, at or near 40%. Conservative Republicans strongly favor Perry over Romney, but liberal and moderate Republicans support the two about equally. Perry's support is also above average among religious Republicans.

In addition to liberals and moderates, Perry is also relatively weak among young Republicans and those residing in the East. Paul continues to demonstrate stronger appeal to young Republicans, and limited appeal to those aged 50 and older.

Palin, Giuliani Also Trail Perry

While the eight announced candidates continue to campaign in key early primary and caucus states, Sarah Palin and Rudy Giuliani are two prominent Republican politicians who have indicated they are still contemplating getting into the race. Palin and Giuliani each receive about 10% of the vote when included in the nomination preference question, with Perry still holding a significant lead over Romney, 25% to 14%, on this measure.

Last month, Romney and Perry essentially tied in preferences among the full list of candidates and potential candidates.

Implications

Perry's official entry has shaken up the Republican race, making him the new leader for the party's nomination. Gallup also finds Perry generating strong positive intensity among Republicans familiar with him, suggesting he has a strong initial base with potential to grow, given his below-average recognition.

Still, he, like Romney before him, rates as a weaker front-runner than those in prior GOP nomination contests. Perry will attempt to avoid the same fates as late-entering candidates in the last two nomination contests -- Fred Thompson in the 2008 Republican field and Wesley Clark in the 2004 Democratic field. Both created a buzz surrounding their potential candidacies, and ranked among the national leaders upon entering the race. However, both fared poorly in early primaries and caucuses and soon after ended their candidacies.

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