Texas Governor Rick Perry speaks during "The Response", an event billed as a call to prayer for the nation in crisis, at Reliant Stadium in Houston August 6, 2011. Perry will announce on Saturday that he will run for the 2012 Republican nomination for US president, CNN reported on August 11. Picture taken August 6, 2011. [Photo/Agencies]

HOUSTON - Texas Governor Rick Perry, a staunch conservative with a Washington outsider's resume, will seek the 2012 Republican nomination for US president, his spokesman said on Thursday, adding a top contender to the party's field of hopefuls.

"He will make a definitive announcement on Saturday for the race," Perry spokesman Mark Miner said. Asked if Perry is indeed joining the race, Miner said, "Yes."

Perry's long-awaited entry promises to reshape the crowded race for the Republican nomination, placing him instantly at or near the top and potentially pushing out several candidates who have failed to gain traction in poll ratings or fundraising.

The eventual Republican nominee will seek to deny Democratic President Barack Obama a second term in office in the November 2012 election. Former Massachusetts Governor Mitt Romney is the early front-runner for the nomination but is seen as vulnerable.

"I think Perry will shoot to the top of the polls right away, and be neck and neck with Romney," said Cal Jillson, a political scientist at Southern Methodist University in Texas.

His campaign confirmed he would run hours before a Thursday night debate among eight other Republican hopefuls in Iowa. His formal announcement on Saturday may steal the spotlight from the Iowa straw poll, a mock election seen as an early test of the candidates' strength, also taking place that same day.

Opinion polls put Perry in the top tier of Republican candidates. He has the political background as Texas' longest-serving governor and fundraising acumen to be a formidable challenger to Obama. He has never lost an election.

A Christian conservative who said he felt "called" to a presidential run, Perry also touts a strong job-creation record in Texas. This could allow him to bridge the gaps between Republicans more focused on social issues such as opposition to gay marriage and abortion, the new activist Tea Party fiscal conservatives and the party's more centrist pro-business wing.

His formal announcement will come a week after Perry led a religious rally that drew tens of thousands of people to a stadium in Houston last Saturday. Religious conservatives play a big role in the Republican nominating race.

TEXAS ECONOMIC RECORD

In a campaign focused on a lagging economy and stubbornly high unemployment, Perry is expected to quickly vie with Romney for front-runner status among the pro-business wing.

Perry, a critic of federal power, took over as Texas governor from George W. Bush after Bush won the 2000 presidential election, giving him the visibility and fund-raising network to make a successful entry into the race, even though it comes months after other leading contenders.

Analysts said Perry's entry could hasten the departure of candidates such as former Minnesota Governor Tim Pawlenty and former Pennsylvania Senator Rick Santorum, who have failed to raise much money or rise above single digits in opinion polls.

A Perry candidacy could also steal support from Minnesota congresswoman Michele Bachmann, a favorite of the conservative Tea Party movement who also is a religious and social conservative, replacing her as Romney's top rival.

"The polls may not show it right away, but most Republicans are going to recognize that Michele Bachmann is not likely to win the nomination or the election, whereas Romney and Perry have a decent chance to do both if the economy continues to do badly," said Larry Sabato, director of the University of Virginia Center for Politics.

"Parties tend to get serious when they realize that they have a real chance to win," he said.

A CNN/ORC poll of Republican voters on Thursday put Perry in second place among candidates or potential candidates for the party's presidential nomination, behind only Romney.

Romney had the support of 17 percent and Perry was at 15 percent in the poll, with no other Republican above 12 percent. The findings were based on answers from 449 Republican voters and had a margin of error of 4.5 percentage points. The telephone poll was conducted August 5-7.