WASHINGTON — For Libertarian candidate Gary Johnson, Election Day arrives on Sept. 26 — the date of the first presidential debate.

The former New Mexico governor and noted advocate for legal marijuana has hit a respectable 10-plus percent in some national and state polls, raising the hopes of disaffected voters unhappy with the major-party offerings of Donald Trump and Hillary Clinton.

Johnson’s trajectory in the year of the outsider still is well short of the 15 percent needed to make the debates, a threshold no third-party candidate has managed since Texas billionaire H. Ross Perot won nearly 19 percent of the popular vote in 1992. Perot made it onto the debate stage with Republican George H.W. Bush and Democratic challenger Bill Clinton, who won the presidency.

Johnson’s backers see it as a critical milestone, though one that seems to be fading with each passing day.

Seasoned political analysts tend to see third-party challenges like Johnson’s as a perennial fantasy, an expression of protest more than attachment to any particular candidate. In this year of widespread disenchantment, however, Johnson is making a serious bid for respect.

“I would not be doing this if there were not the opportunity to win,” Johnson said in a recent appearance on NBC’s Meet the Press. “But the only opportunity I have of winning is to be in the presidential debates.”

Johnson’s campaign says he has no intention of playing the spoiler role that many assigned to Perot, who created enough space for Clinton to come within 4 percentage points of upsetting Bush in Texas, the president’s home state.

Though Johnson remains invisible to large swaths of voters, he is the only third-party candidate on the ballot in all 50 states. Polls also put him far ahead of any other alternative candidate, including the Green Party’s Jill Stein, who registers in the low single digits.

More encouraging to those looking for a breakthrough, Johnson has gained far more traction this year than he did in 2012, when he won less than 1 percent in his first run for president.

For Johnson or any other dark horse candidates hoping to shake up the 2016 election, getting on the debate stage is threshold for relevance.

“He’s tantalizingly close,” said Texas GOP operative Steve Munisteri. “But he’s probably going to miss it.”

Another path to third-party relevance is impact, though political analysts say Clinton’s current lead in the Electoral College — the one that counts on Nov. 8 — diminishes any third party’s ability to make a difference, even as surveys show that nearly half of American voters would like a third choice.

George W. Bush’s 2000 election victory over Al Gore — decided by a few hanging chads in Florida — widely is believed to have been decided on the strength of Green Party nominee Ralph Nader, an icon of the left.

Polls also show that despite Johnson’s brand as a budget hawk in the Republican Party, his positions on abortion, gay marriage and legal marijuana have seen him siphon off support from Clinton almost as much as Trump.

To Johnson, that’s a sign of broad appeal. Still, the numbers belie the popular notion that the two leading candidates’ negatives could make 2016 a breakout year for an alternative party.

At the moment, the race just is not that close in some of the critical swing states where it really matters.

Moreover, a number of polls in battleground states such as Florida, Ohio and Pennsylvania show little difference in the spread between Clinton and Trump when Johnson and Stein are added to the mix. A recent Quinnipiac University poll in Pennsylvania, for example, gave Clinton a 52-to-42 percent lead over Trump in a head-to-head matchup. When voters were asked about a four-way ballot including Johnson and Stein, Clinton and Trump’s numbers both suffered, but Clinton’s lead shrank by only one point, 48-to-39 percent.

To Quinnipiac pollster Peter Brown, that difference is “statistically insignificant,” meaning that neither alternative candidate affected the overall outcome.

Even in Texas, a Republican state with a strong libertarian streak, Johnson has not been a factor in pollsters’ calculations. A recent Public Policy Poll in Texas, for example, gave Trump a six-point lead over Clinton — 50-to-44 percent — a narrow margin for a Republican in a deep red state. With Johnson and Stein included in the poll, Trump’s lead became 44-to-38 percent — still a six-point spread.

Johnson polled at 6 percent in the Texas poll; Stein got 2 percent; and anti-Trump conservative Evan McMullin got less than 1 percent. Where Clinton and Trump were concerned, it appeared to be a wash.

“(Johnson) is taking close to the same amount of votes from Democrats as he is from Republicans,” said Munisteri, a former chairman of the Texas Republican Party and a close ally of Kentucky U.S. Sen. Rand Paul, the son of former Texas U.S. Rep. Ron Paul, a libertarian icon who also ran for president. “I actually think Stein potentially has a greater effect than Johnson, because she only hurts Clinton.”

While comparisons to Ron Paul and Perot are inevitable, Johnson does not seem to have the same loyal following as either of those two enigmatic figures.

He also gives both sides something not to like. Going against liberals, he favors repealing Obamacare and opposes most gun restrictions; against conservatives, he favors a “pathway to citizenship” for some undocumented immigrants; against small-government libertarians, he favors mandatory labeling of genetically modified foods.

Some analysts say the campaign lacks the sort of overarching theme it would take to burst into the big leagues or become a major political force.

“Gary Johnson has blown a big opportunity here,” said Democratic strategist Harold Cook, former executive director of the Texas Democratic Party. “He keeps acting like the nominee of a minor third party … He’s busy being Gary Johnson. He’s talking about legalizing weed and stuff you would expect a libertarian candidate to talk about, which kind of is the death knell for him. He’s standing in his own way in preventing Republicans from seeing him as a viable third-party alternative.”

kevin.diaz@chron.com

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