Louisiana Gov. Bobby Jindal addresses the Nebraska Republican Convention in Grand Island this weekend. (Nati Harnik/AP)

Three years ago, Louisiana Gov. Bobby Jindal got his first big chance in the national spotlight and bombed. His response to President Obama’s first State of the Union address was uniformly panned. “Not ready for prime time” was a common critique.

But Jindal (R), who is often mentioned as a vice-presidential contender on Mitt Romney’s short­list, is proof that there are second acts in American politics.

On Monday, Jindal, who backed Texas Gov. Rick Perry in the primary contest, joined Romney for a high-dollar fundraising luncheon with supporters in Baton Rouge, fueling more debate about his chances of becoming the running mate.

Romney announced in a note to supporters last week that he will name his pick before the Republican National Convention in August, dubbing the ticket “America’s Comeback Team.”

Asked recently about his vice-presidential prospects, Jindal offered the classic non-response.

“We’re not going to speculate. I’ve said this for the last several weeks. We’re not speculating. We’re not commenting on that,” he said on NBC’s “Meet the Press,” referring questions to the Romney campaign. “No disrespect to Joe Biden, nobody’s going to the voting booth and voting based on who’s vice president.”

Yet social conservatives are looking closely at Romney’s choice for signs that he wants to assuage their concerns about issues that are important to them, such as their opposition to abortion and gay rights. Jindal would fit that bill.

A darling of social conservatives, he has reworked his image by tackling major problems, including the Gulf of Mexico oil spill in 2010, and by being one of the most vocal critics of the Obama administration’s policies on health-care reform and the economy. And he has emerged as one of Romney’s most visible and aggressive surrogates, going head to head with Democrats on Sunday roundtable talks and traveling the country to rebut Obama on his tour of Midwestern states.

Elected in October to his second term with 66 percent of the vote, he has steadily polled in the mid-50s. Asked recently about being on the ticket, he gave the classic non-answer to a question about whether he would serve if asked.

In the primaries, Romney struggled among evangelicals, routinely losing that key voting bloc to former senator Rick Santorum (Pa.), who frequently campaigned from the pulpit of churches and whose insurgent run was powered by a string of wins in the South.

Since the primaries, Romney has made overtures to social conservatives, including a speech at Liberty University in May, and his team seemed to cave to evangelicals who balked at his choice of an openly gay national security campaign adviser — Richard A. Grenell, who resigned after being sidelined by the campaign.

With his teenage conversion from Hinduism to Catholicism and ironclad antiabortion views, Jindal would excite the ­social-conservative base, which is not sold on Romney.

“Jindal would be very, very well received among evangelicals. I hear nothing but rave reviews from evangelicals in Louisiana about how he has given them access and developed a relationship that is better than any other governor that they have ever had. What most evangelicals have been saying to the campaign is that it has to be somebody pro-life,” said Richard Land of the Southern Baptist Convention. “And he also counterbalances the elitist claim [because] he is an up-from-the-ranks guy, and it helps to have someone on the ticket who is from Main Street, not Wall Street.”

Jindal is one of the youngest governors in the country, a symbol of a new vanguard of Republicans who are managing a state in real time, dealing with natural disasters and budget shortfalls while hewing closely to a small-government philosophy.

He recently cut $859 million from Louisiana’s Medicaid program and has said that he would not expand it or create a state exchange.

Like House Budget Chairman Paul Ryan (R-Wis.), Jindal has a reputation as a disciplined policy wonk, nerdy but not too academic.

“He has a good grasp of policy, he is nonwhite, he is relatively young, he is part of the new conservative vanguard like [Sen. Marco] Rubio and Ryan, who can speak with eloquence about small government,” said Brian J. Brox, a political scientist at Tulane University. “In the aftermath of Hurricane Katrina, he was seen as a Mr. Fix-It. Someone who would have the facts and be on top of everything and help rebuild the state.”

Romney, who spent the weekend in Wolfeboro, N.H., mulling over his choices, is campaigning on a similar theme, and a Romney-Jindal ticket would allow Republicans to run as Washington outsiders.

Jindal’s record on health care could give Romney some cover on that issue. At age 24, he was appointed to head Louisiana Department of Health and Hospitals.

“This campaign will come down to health care and the economy. Jindal, he could talk about health care and be able to draw that fire away from Romney on ‘Romneycare’ in Massachusetts,” said Tyler Harber, a Republican consultant. “He could also talk about immigration and he would provide a different generational view of what American could be in a way that Romney could never be seen to provide.”

Democrats are likely to highlight Jindal’s record on abortion rights — he has said he opposes it in all cases. And they are likely to paint him as a hypocrite for criticizing the $830 billion Recovery Act, yet using it to plug budget holes.

Jindal, who is considered a wunderkind, seems to fit the first rule of a vice presidential pick: First do no harm.

“He is as clean as the day is long, just go look into his life, you’ll be bored. The kid is a Boy Scout,” said Roy Fletcher, a Republican political consultant based in Louisiana who has known Jindal for a dozen years. “He is also a brilliant campaigner. You can’t drive him off a message if you had a peach truck. If he gets it, you got a hellacious candidate for VP.”