Gary Johnson won't be attending Monday's presidential debate—the first of the 2016 election cycle—but the Libertarian candidate hasn't stopped fighting for inclusion.

In an op-ed published in the New York Daily News Sunday morning, Johnson advocated against the "two-party duopoly" of the Commission on Presidential Debates, a nonprofit organization that oversees presidential and vice-presidential debates. He accused the commission of partisan politics, shutting out third-party candidates like himself and Green Party's Jill Stein.

"Among truly independent voters, our ticket leads with 31 percent support, versus 24 percent for Hillary Clinton and 24 percent for Donald Trump, according to NBC News," Johnson noted in the op-ed piece. "Among millennial voters, according to Quinnipiac University, I’m in a statistical tie with Clinton, 31 percent to 29 percent. Among the military, the tables are turned, with Trump and me tied.

"This is everything that is wrong with American politics.

"Here I am, polling at higher numbers than Ross Perot had in 1992, when the commission let Perot debate George H.W. Bush and Bill Clinton," Johnson wrote.

In 2015, the commission imposed a 15 percent polling threshold for debate inclusion—a mark that's considered too high for third-party candidates. According to Johnson, the Annenberg Working Group on Presidential Debate Reform favored lowering the polling threshold to 10 percent for the first debate.

Still, Hillary Clinton and Donald Trump will square off Monday night at HofstraUniversity, and more than 100 million viewers are expected to tune in.

In a joint lawsuit Johnson and Stein filed last year against the commission, the two candidates alleged violations of antitrust laws and the First Amendment to undermine competition in the presidential debates.

"To be excluded from the debates is 'an electoral death sentence,' the lawsuite asserted. "The media gives non-duopoly, non-major party candidates little or no coverage, and they cannot afford significant, if any national advertising. Hence, they are denied the free, enormous coverage received by the duopoly party candidates through the debates, and they are marginalized in the minds of most people in the U.S. and the media, and considered to be less than serious, peripheral, and perhaps even frivolous candidates."

A judge threw out the complaint in August, saying the commission is a private nonprofit organization, not a government entity, and therefore complaints about the First Amendment are null.

Still, Johnson could earn a podium at the second or third presidential debates, if the criteria set forth by the commission are met.