US Republican presidential candidate Mitt Romney addresses supporters during a campaign rally at a local business in Las Vegas, Nevada.

Mitt Romney's faith emerged as little more than a curiosity on the US campaign trail, but with the Republican nomination securely in his grip, are American voters now ready for a Mormon president?

The candidate made history late Tuesday as the first from his religion to win the nomination of a major political party, and the achievement helps show how far the acceptance of Mormonism has come since its founding in the United States nearly two centuries ago.

A President Romney could be a golden opportunity for a church aiming to broaden its base across the United States and internationally, but it is also fraught with risk.

Romney, who outlasted several rivals in a bruising primary battle, has become the unlikely flagbearer of a Republican movement heavily influenced by evangelical Christians, some of whom have called Mormonism a “cult.”

But despite persistent scepticism about the faith - a Bloomberg News poll from March shows more than one in three Americans hold an unfavourable view of the Mormon church - associate professor Brandon Rottinghaus of the University of Houston said on Wednesday he thinks Americans are ready for a Mormon president.

“There will be a small segment of evangelical voters who won't accept the Mormon faith as a tenet of Christianity, but most voters will be tolerant,” Rottinghaus told AFP.

“The big challenge for the Romney campaign was to get through the Republican primary process without a religious uproar, a task they have completed.”

The Church of Jesus Christ of Latter-day Saints has remained silent on the presidential campaign, even though Romney's milestone could be seen as a plus for Mormonism.

“The church's political neutrality is well established, and we have no interest in providing commentary on a political race,” Eric Hawkins, a spokesman for the Utah-based church, said after Romney clinched the nomination with a win in Texas.

The breakthrough is tempered by the historic nature of the 2008 race, which achieved several firsts: Americans elected Democrat Barack Obama as their first black president, Sarah Palin became the first female Republican vice presidential pick, and Hillary Clinton almost earned her party's nomination.

And in 2000, Democrat Al Gore very nearly won the White House with Joe Lieberman, an orthodox Jew, as his running mate.

“Primary audiences in both parties are used to seeing diversity among the pool of potential nominees,” Rottinghaus said.

Romney is not the first Mormon to seek the White House. Founder Joseph Smith ran in 1844, in part to press for greater civil liberties for members of his nascent church.

And Jon Huntsman, a former Utah governor, was a candidate this year, but his campaign failed to gain traction and he dropped out in January.

With the general election now in full swing, Obama and Romney are hammering each other over economic policy. But character and personal background form a piece of the puzzle, and Romney's faith will likely come under some scrutiny.

For many Mormons, like Aaron Sherinian, a public relations professional in Washington, Romney's nomination marks “a chance to talk about who we are, what we believe, and why service to our country is at the heart of our community.”

But “religion isn't the issue on the ballot,” Sherinian told AFP.

“This election is going to be more about what's happening to people's pocketbooks than what's being said over pulpits.”

Romney has spoken little about his religion, other than portraying himself as a man of faith with beliefs similar to those of other Christians.

In 2007 during his first presidential run, Romney gave an address about the role of faith in America, but he mentioned Mormonism just once.

Earlier this month he gave the commencement speech at Liberty University, America's largest evangelical Christian college, but spoke only in broad Christian terms.

Some of the stigma faced by Mormons stems from the faith's seemingly secret traditions - non-Mormons are barred from entering temples, for example.

The church is known for its missionaries - both Huntsman and Romney worked abroad to spread the faith - as well as its past practice of polygamy and strict rules against alcohol, tobacco and caffeine.

There are six million Mormons in the United States, where the faith was founded, and three out of four describe themselves as conservative.

Sherinian said one political message the Mormon church openly promotes is the responsibility to learn about candidates and participate in the political process, “whether the candidate for the White House is Mormon or Muslim or Methodist.” - AFP