Illinois Rep. Adam Kinzinger announced yesterday that he would not vote for Donald Trump, becoming one of the few sitting congressman to refuse to support the GOP nominee. (Full disclosure: Kinzinger represents my congressional district.)

Kinzinger stressed that he wouldn't vote for Hillary Clinton and was unsure if he would cast a vote for president at all.

Politico:

Kinzinger told CNN he went to the Republican National Convention and had hoped to be able to endorse Trump by the end of it. However, the former Air Force pilot said after Trump’s comments on NATO and his spat with Khizr Khan, the father of a fallen soldier who spoke at the Democratic National Convention, he doesn’t see how he could endorse him.

“Donald Trump is beginning to cross a lot of red lines of the unforgivable in politics. I'm not going to support Hillary, but in America we have the right to skip somebody,” he said on CNN. “That's what it's looking like for me today. I don't see how I get to Donald Trump anymore.”

Kinzinger joins a growing list of Republicans who have said they will not support their party’s nominee for president. However, unlike many others in the group, Kinzinger is running for reelection. Earlier this week, New York Rep. Richard Hanna said he would back Clinton, but he is retiring from Congress.

Kinzinger did not say who he would vote for instead.

"There's a bunch of people on the ballot. There's a write-in option. I don't agree with Hillary Clinton on a lot of things, most things, probably almost all things, but Donald Trump, I don’t know what he stands for in foreign policy.”

What makes Kinzinger's defection significant is that he is running unopposed for re-election. There is no political reason to refuse to vote for the nominee. The Iraq War veteran can't support someone like Donald Trump.

In 2014, the Club For Growth tried to primary the congressman by running a Tea Party candidate against him. Kinzinger won 78% of the vote. Kinzinger may not be the ideal candidate for those who are calling themselves conservative these days, but for the 16th congressional district in the heartland of Illinois, he's plenty conservative enough.