This combination of file photos shows the silhouettes of Donald Trump and Hillary Clinton. (AFP/Getty Images)

RICHMOND — Democrat Hillary Clinton has a comfortable lead over Republican Donald Trump in the battleground state of Virginia, a new poll finds ahead of their first debate Monday, but Libertarian Gary Johnson is picking off millennial supporters from both.

Clinton is leading with likely Virginia voters 48 percent to Trump’s 38 percent in a head-to-head matchup, according to a survey released Monday by the Wason Center for Public Policy at Christopher Newport University.

But with three third-party candidates in the mix, Clinton has 39 percent to Trump’s 33 percent. Johnson attracts 15 percent, while Green Party nominee Jill Stein and independent Evan McMullin each have 3 percent, according to the poll, which has a margin of error of 3.9 percentage points.

Voters 18 to 34 years old prefer Clinton (52 percent) over Trump (30 percent) in a two-way race. But when Johnson is factored in, many of those millennial voters opt for the Libertarian. Clinton still leads, with 34 percent, but Johnson draws 27 percent and Trump takes 23 percent.

The CNU poll is slightly better for Clinton and more substantially so for Johnson compared with how they fared in a pair of Virginia surveys released last week.

Gary Johnson, 2016 Libertarian presidential nominee, listens to questions from audience members during a campaign event at Purdue University in West Lafayette, Ind, Sept. 13. (Luke Sharrett/Bloomberg)

A Roanoke College poll found Clinton leading with 44 percent to Trump’s 37 percent among likely voters, while a Quinnipiac University poll found Clinton ahead by a margin of 45 percent to 39 percent. Johnson garnered 8 percent support in both of last week’s polls, while Stein stood at 1 percent in each.

[Clinton has modest lead over Trump in Virginia, new polls say]

“Clinton’s lead over Trump in Virginia is strong,” said Quentin Kidd, director of the Wason Center. “It is not only built upon her own partisan identifiers, but also on a very strong showing from vote-rich Northern Virginia, a large gender gap, and stronger support than Democrats usually get from college-educated white voters and white women.”

Surveying voters on character issues, the CNU poll found 54 percent said Clinton cannot be trusted with classified information, while 53 percent said Trump is a racist.

“That more than half think that Donald Trump is a racist is astounding,” said Rachel Bitecofer, assistant director of the Wason Center. “That tells you all you need to know about why a diverse state like Virginia is beginning to fall out of reach of the Trump campaign.”

In military-heavy Virginia, more voters think Clinton would make a better commander-in-chief than Trump, 50-40 percent, with female voters saying so by a 2-1 margin. But military voters prefer Trump in that role 48 percent to 39 percent.