LAS VEGAS — Former New Mexico Gov. Gary Johnson is campaigning to win the White House as a Libertarian after receiving scant attention in the Republican presidential race.

Johnson easily became the party’s presidential nominee at the Libertarian national convention in Las Vegas on Saturday. He said he hopes to appeal to voters fed up with the traditional two-party system in November.

Johnson was a longshot candidate for the Republican presidential nomination when he announced in December that he would instead pursue the Libertarian ticket.

He won 70 percent of the vote on the first ballot in Las Vegas, an unusual showing of support. His closest challenger, R. Lee Wrights of Texas, finished with 25% of the ballots. In 2008, Libertarian delegates needed six rounds of voting to pick a presidential nominee.

“I am honored and I just want to pledge that no one will be disappointed. We’re going to grow the Libertarian Party,” Johnson said after the vote.

There were no complaints of carpetbagging among the delegates despite Johnson’s sudden embrace of the Libertarian movement after his Republican loss. Some noted that his gubernatorial experience could lend the party more credibility among Republican and Democratic voters.

“I am convinced that Gary Johnson will be an exceptional candidate,” said chairman Mark Hinkle. “Libertarians will show voters how we can make government small while dramatically increasing jobs, lowering taxes and scaling back government debt.”

Johnson is fiscally conservative but supports such liberal causes as legalizing marijuana, immigration reform and abortion rights.

During a recent campaign stop in Las Vegas, Johnson told The Associated Press that he plans to court Democratic voters who support legalized marijuana, as well as Republican voters unhappy with former Massachusetts Gov. Mitt Romney’s health care law.

Johnson was excluded from all but two GOP presidential debates and barely registered in polls. Moving forward, he said he hopes to reach 15 percent approval in national polls and at least win New Mexico in November. Nevada could also be in play, he said.

Johnson was elected New Mexico’s governor in 1994.

Elisheva Levin, vice chair of the Libertarian Party in New Mexico, said she always viewed Johnson as a Libertarian and voted for him for governor.

“He governed from a Libertarian stance,” she said.