Rick Perry, former Texas governor, running for 2016 Republican presidential nomination

Former Texas governorRick Perry opened his second bid for the U.S. Republican presidential nomination Thursday, pledging to "end an era of failed leadership" and hoping this campaign will go better than his last one.

Perry announced his candidacy in a humid airport hangar in the company of fellow veterans and a hulking C-130cargo planelike the one he flew for the U.S. air force.

With Perry in the contest, and confirmation earlier on Thursday that former Florida governor Jeb Bush will run, 11 major candidates now are vying for the Republican nomination and still more are expected to join.

"Leadership is not a speech on the Senate floor," he said. "It's not what you say. It's what you do."

That was an indirect swipe at Texas Senator Ted Cruz, Florida Senator. Marco Rubio and other rivals with little to no executive experience.

Perry said that, if elected, he would authorize the Keystone XL pipeline on his first day in office.

Jeb Bush set to enter

Bush, the brother of former U.S. president George W. Bush and son of former president George H.W. Bush,will announce his bid to become the Republican presidential nominee on June 15 in Miami, Reuters reported Thursday.

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As Perry returns to presidential politics, the question remains: Will he get another solid chance?

"It's going to be hard to make a first impression a second time," said Ford O'Connell, a Republican strategist in Washington.

Despite his brain freeze on a Michigan debate stage in November 2011 he forgot the third federal agency he promised to close if elected, then muttered "Oops" Perry still has the policy record that made him an early force last time.

Perry left office in January after a record 14 years as governor. Under him, the state generated more than a third of America's new private-sector jobs since 2001.

While an oil and gas boom fuelled much of that economic growth, Perry credits lower taxes, restrained regulation and limits on civil litigation damages. He also pushed offering economic incentives to lure top employers to Texas and repeatedly visited states with Democratic governors to poach jobs.

Republicans who have announced 2016 presidential campaigns:

• Dr. Ben Carson
• Ted Cruz
• Carly Fiorina
• Lindsey Graham
• Mike Huckabee
• George Pataki
• Rand Paul
• Marco Rubio
• Rick Santorum

Pending:Jeb Bush

Rumoured: Chris Christie, Bobby Jindal, John Kasich, Donald Trump, Scott Walker.

Perry was thought to be a cinch for four more years as governor in 2014, but instead turned back to White House ambitions. His effort may be complicated this time by a felony indictment on abuse of power and coercion charges, from when he threatened then carried out a veto of state funding for public corruption prosecutors. That came when the unit's Democratic head rebuffed Perry's demands that she resign following a drunken driving conviction.

Perry calls the case against him a political "witch hunt," but his repeated efforts to get it tossed on constitutional grounds have so far proved unsuccessful. That raises the prospect he'll have to leave the campaign trail to head to court in Texas.

Wearing comfortable shoes

Perry blamed lingering pain from back surgery in the summer of 2011 for part of the reason he performed poorly in the 2012 campaign. He has ditched his trademark cowboy boots for more comfortable footwear and wears glasses that give him a serious look.

Perry also travelled extensively overseas and studied policy with experts and economists at Stanford University's Hoover Institution. He met such business moguls as Warren Buffett and Rupert Murdoch.

Lately, Perry has travelled to Iowa, which kicks off presidential nomination voting, more than any Republican White House candidate.

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"People realize that what the governor did in the high-profile debate, stumble, everyone has done at some point in their lives," said Ray Sullivan, Perry's chief of staff as governor and communications director for his 2012 presidential bid. "I think he's already earned a second look, particular in Iowa."

"I think he's kind of been freed up to be Rick Perry again," said Brendan Steinhauser, a Texas political consultant who was director of state and federal campaigns for tea party-backed FreedomWorks. "That's going to give him a lot of freedom to do what he does best, which is talk to voters one-on-one, shake hands, do the small meetings."

As an underdog, Perry has visited out-of-the-way places in Iowa, often travelling with a single SUV rather than the busloads in his 2012 entourage. Steinhauser said Perry shouldn't "start out trying to be larger than life."

One thing Perry hopes to emulate from 2012 is his fundraising, when he amassed $18 million US in the first six weeks. He has strong donor contacts nationwide as a former Republican Governors Association chairman. However, his indictments may cause some to hesitate to write him cheques.

Perry's camp notes that many past Republican candidates, including Mitt Romney in 2012, rebounded to win the party's presidential nomination after failing in a previous bid. But O'Connell, the Republican strategist, said the 2016 field is "extremely talented and deep" compared to four years ago.

"For him to win the nomination," O'Connell said, "he's going to have to be great, but a lot of people are going to have to trip and fall along the way."