WASHINGTON (Reuters) - In Republican Mitt Romney's bid for the White House, there are the obvious obstacles: namely a sitting president, Democrat Barack Obama, and his massive campaign organization.And then there are the less predictable hurdles - such as Gary Johnson, a self-effacing former New Mexico governor who could complicate Romney's efforts to challenge Obama in New Mexico, Colorado and Nevada in the November 6 election.
Johnson, 59, is the Libertarian Party's nominee for president and, by most measures, a fringe candidate. He wants to cut the U.S. government's budget by a whopping 43 percent and legalize marijuana, and he struggles to persuade pollsters to even include him in their surveys of voters.
In a campaign in which the two main contenders and their allies could raise nearly $1 billion each, Johnson has raised a little more than $800,000 through the end of April.
But Johnson, who left the Republican Party in December after his presidential bid could not get traction there, has entered the summer campaign season carrying just enough weight to be a factor in the fall.
He is likely to be on the ballot in all 50 states and has qualified to receive matching campaign funds from the U.S. government. Most significantly, he appears to be picking up enough support in the western United States to affect the battle between Obama and Romney - most likely in Obama's favor, according to analysts who say much of the support Johnson could get probably will come from potential Romney voters.
Like Texas Representative Ron Paul, Johnson is trying to tap into some voters' rising anxiety over a soaring U.S. government deficit and concerns that Washington has too much of a role in Americans' lives.
Johnson - who turned a plumbing and remodeling business into one of New Mexico's largest construction companies before selling it 1999 - rejects the notion that he could be a third-party spoiler for Romney, as Ralph Nader was to Democrat Al Gore in 2000 and Ross Perot to Republican George H.W. Bush in 1992.
He envisions a scenario in which his campaign will get a boost in September, after Paul - a Republican who also calls for an extremely limited government - is expected to leave the presidential race. Although Romney has clinched the Republican nomination, Paul remains in the race, which could give him a chance to influence the party's platform at its convention in Tampa, Florida, in late August.
Johnson, a marathon-runner, hopes to inherit Paul's small but devoted core of fans as the presidential race enters its final stretch.
"I can't imagine a Ron Paul supporter who is going to support Romney," Johnson said last week during a visit to Washington, adding that Romney envisions a larger government than Paul supporters favor.
ALTERING THE RACE
In the state-by-state race for the presidency, Romney's prospects would brighten considerably if he could win New Mexico, Nevada and Colorado, politically divided states that Obama won in the 2008 election.
Winning one of those states would reduce the pressure on Romney to win larger, hotly contested states such as Ohio and Virginia.
For Romney, it is a tall order. New Mexico, Nevada and Colorado have experienced significant growth in Latino voters and a decline in white, working-class voters in recent years, a trend that generally favors Obama.
By the election, Johnson's campaign could become a headache for Romney in those three states.
Nearly anonymous nationwide, Johnson is popular in his home state. A survey of New Mexico voters in May, taken by Patriot Majority USA, a Democratic group, found Johnson polling at 12 percent there, compared with Obama's 48 percent and Romney's 35 percent.
"The presence of Gary Johnson on the ballot significantly undercuts Romney's long-term viability" in New Mexico, said Craig Varoga of Patriot Majority.
Others say that Johnson's showing reflects an unhappiness with Obama and Romney, and that his support will shrink as election day approaches.