In a poll released this week, 52 percent of veterans said they would vote for President Trump, while 42 percent backed former Vice President Joe Biden. Others favored a third party candidate, or planned to not vote.
The poll was by Military Times and the Institute for Veterans and Military Families at Syracuse University.
"I've never seen it this close in previous years," said Rosalinda Maury, Director of Applied Research and analytics.
In 2016, Trump was favored by 60 percent of veterans who voted, according to exit polling. In the new poll, older vets still had a clear preference for the President, while younger veterans, female and minority veterans, and former officers favored Biden.
"When you start looking at these subpopulations, you do see some difference," Maury said.
Gary Aiken is among the 59 percent of veterans over the age of 54 backing Trump. A 71-year-old Vietnam veteran from the mountain community of Swannanoa, North Carolina, Aiken owns a small sign and graphic design company.
"The veterans that I know that interact with are basically saying that they're going to vote for Trump," Aiken said. He credited the President for improving VA health care and the economy.
"And I think, for me, personally, it has to do with the America that I knew growing up versus the America that Biden and some of his cronies envision, which is certainly not what I would want for my grandkids," he said.
But Trump's volatile behavior and his controversial comments about veterans and service members haven't played well with many younger veterans, including former Navy SEAL Dan Barkhuff, now an emergency room doctor in Vermont.
"I have many issues with Trump, but the thing that started it all was just his dishonesty," said Barkhuff, who described himself as a conservative.
"I was in the Naval Academy when Clinton was the Commander-in-Chief and Monica Lewinsky and all that kind of stuff, "Barkhuff said. "I didn't like that either … and there were all these arguments made by people who are still in politics frankly that you can't have a Commander-in-Chief who's dishonest with the troops he's supposed to lead."
Barkhuff founded a group called Veterans for Responsible Leadership to, in some sense, persuade other veterans that it's okay not to vote for Trump.
And he agreed to record some bare-knuckle ads for the Lincoln Project, the Republican anti-Trump group that specializes in ads goading the president.
"I'm a pro-life, gun-owning combat veteran, and I can see Trump for what he is - a coward," he said in the commercial. "We need to send this draft-dodger back to his golf courses. The lives of our troops depend on it."
The new poll follows an apparent trend. A poll this summer by the same groups found a slight edge for Biden among active-duty troops. And another recent poll of veterans by Morning Consult yielded a similar result.
The contentious campaign has also spurred non-partisan activism among veterans. Afghanistan veteran and digital media CEO Greg Behrman has joined forces with 10 other high-profile veterans to promote voting.
He said they were disturbed by widespread voter suppression efforts and felt it was an extension of their military service to fight that.
"None of us took any pleasure in having to do this," Behrman said. "We wanted it to feel like every leader was doing his part during a high stakes time for our country, to stand by what it means to have a free, fair and safe election. But feeling like that was under threat and feeling like the lights were blinking red, it felt really important just to say, 'Hey, you know, we have a stake in this, and we have a perspective that we think is worth sharing.'
Behrman said some in his group are liberal, others conservative. But he said the point isn't whom to vote for, it's that everyone should be allowed to vote.
