The Libertarian presidential candidate, Gary Johnson, achieved a major milestone on Saturday. Rep. Scott Rigell from Virginia became the first sitting Republican member of Congress to endorse a third-party candidate this election season. In an interview with the New York Times, Rigell said statements made by Donald Trump influenced his decision.

“I’ve always said I will not vote for Donald Trump and I will not vote for Hillary Clinton,” Rigell said. “I’m going to vote for the Libertarian candidate.”

Rigell still considers himself a Republican despite endorsing a Libertarian for president. If the party continues to welcome Trump and his policy ideas as their own, Rigell said he will leave the party and register as an independent.

Prior to Rigell’s first successful run for office in 2010, he spent six years serving as a U.S. Marine before opening a pair of car dealerships in Virginia. Rigell is a three-term Congressman and will not be running for re-election this year.

U.S. Rep. Scott Rigell [Photo by Alex Wong/Getty Images]

Rigell isn’t the only Republican who refuses to vote for his party’s nominee. His comments about not voting for Trump nor Clinton is uncanny in its similarity to comments made by several other Republicans.

With this endorsement, the door is now wide open for more Republicans to back Johnson and his running mate, former Republican Gov. William Weld from Massachusetts. Republican Rep. Mike Coffman from Colorado could be Johnson’s second congressional endorsement.

On Thursday, Coffman, who’s running for re-election in a competitive district, released an ad mentioning his disapproval for both nominees. The ad doesn’t say who he’ll support, but when asked by a Denver 7 reporter, who he plans on endorsing, Coffman said he’s more focused on his own run for office at the moment — but will consider endorsing a third-party candidate.

“Donald Trump has not earned my support. I’m not going to vote for Hillary Clinton. (I’ve) talked to Gov. Weld on the Libertarian side, and I wouldn’t rule that out,” Coffman said.

Rep. Adam Kinzinger from Illinois is another Republican lawmaker who has publicly said this week that he will not endorse Trump. On Thursday, Kinzinger, who served tours in Iraq and Afghanistan in the Air Force, told CNN’s Wolf Blitzer that Trump’s foreign policy doesn’t add up and his comments directed at Khizr Khan’s family recently were the final straw.

“I’m saying for me personally, how can I support that? Because he has crossed so many red lines that a Commander in Chief, or a candidate for Commander in Chief should never cross. It’s a tough position for me to be in,” he said.

Kinzinger still hasn’t endorsed a presidential candidate.

Rigell isn’t the only Republican lawmaker this week to endorse a candidate that isn’t Trump. On Tuesday, Rep. Richard Hanna from New York wrote in an op-ed published on Syracuse.com that he will be voting for Clinton.

“I find Trump deeply flawed in endless ways,” Hanna said. “A self-involved man who is worth billions yet is comfortable — almost gleefully — using bankruptcy laws to avoid the consequences of his own choices.”

Libertarian presidential candidate Gary Johnson talks to a crowd of 2000 supporters in Salt Lake City, Utah. [Photo by George Frey/Getty Images]

Earlier this week, Johnson nabbed the endorsement of former Minnesota Gov. Jesse Ventura. In an op-ed for Time, Ventura wrote that he likes the Libertarian ticket because they both have experience as governors, and Johnson is socially liberal and fiscally conservative.

“I’m not about to go against my principles now,” he said. “Do I want Trump to be president? No. Do I want Hillary to be president? No. But I want Gary Johnson to be president, and that’s why I’m voting for him.”

Johnson currently has endorsements from 14 current and former elected officials, and one from Daniel Hannan, a member of the European Parliament in the U.K., but he’ll need to add to this list if he wants to be a serious contender for the White House.

Johnson faces an uphill battle to be featured alongside Trump and Clinton on the debate stage at Hofstra University in New York in September. The Real Clear Politics average currently has Johnson at 8.4 percent. He’ll need to cross the 15 percent mark in national polls to qualify for the debate.

The third-party candidates’ climb got steeper this week when a federal judge tossed out a lawsuit filed by Johnson and the Green Party’s Jill Stein alleging violations of the First Amendment and antitrust law if they’re excluded from the debates. Johnson’s campaign said they are still exploring their options, but after receiving his first congressional endorsement from Rigell, maybe his luck is about to turn around.

[Photo by George Frey/Getty Images]