"For our president, who opted out of serving in the military, to attack transgender people for being unfit to serve . . . is the height of hypocrisy," said Roem, 32, a former newspaper reporter. "Transgender military members . . . have done more to serve and protect their country than Donald Trump ever will."
Marshall, a 25-year incumbent in the Prince William County district, which is close to the Marine Corps base in Quantico, said in an interview that he thought it was prudent to expel and bar transgender people from the military.
"The money that would have been spent on costly and risky elective surgeries and decades of synthetic hormones that can cause cancer, in an effort to change sexual appearance, will be much better spent on treating our combat wounded servicemen and our veterans, and on buying equipment to keep our servicemen safe," Marshall said in an email.
The latest flash point in the nation's culture wars illustrates a bind for Roem.
She has said that she doesn't want to be defined as the transgender candidate, even as that status has brought her attention from the media and prospective donors. As her advisers have urged, she has focused her campaign on local issues, such as Route 28 traffic, jobs and education.
But Roem says she can't stay silent in the face of discrimination that she says sends a message to young transgender people that they are "less than" or don't belong. And she says that the time Marshall spends trying to pass conservative, social-issues legislation should be spent addressing local concerns.
"As a transgender person, I find it reprehensible that Delegate Marshall has denigrated the service of transgender Americans who have sacrificed their lives so he can have the freedom to say what he says," said Roem, who included a fundraising appeal in one of her tweets about Trump's ban on Wednesday. "It's about time the people of the 13th District had a delegate who will represent them instead of singling them out, stigmatizing them and trying to make them feel awful about who they are."
Roem said she received a $50,000 donation from Milwaukee County Executive Chris Abele, who chairs the Gay & Lesbian Victory Fund, after Trump announced the transgender military ban. That is on top of the $150,000 she raised for her bid, including an earlier $35,000 from Abele.
Abele, a major donor to LGBT causes, said he was at the White House for an economic development event with Trump, Wisconsin Gov. Scott Walker (R) and others on Wednesday, the day the president made his announcement on Twitter.
Instead of condemning Trump to his face, Abele said, he made the donation to Roem from his smartphone while in the East Room. Then he texted her to say his donation would speak louder than any words could.
"This is one election, but it's a first, and so is the first woman elected, so is the first African American, the first Hispanic," Abele said in an interview. "Transgender candidates being as much of a norm as any other citizen is the best way to prevent policies like a ban on anyone, transgender or otherwise, who want to serve defending this country."
In the past, when asked about Roem's criticisms, Marshall has said that Democrats have long tried and failed to defeat him by painting him as out of touch with his constituents. The district has gone for both Democratic and Republican candidates in other races in recent years, and it voted for Hillary Clinton in November.
On Wednesday, Marshall said he is far from alone in thinking the military is no place for transgender people.
"The decision to end transgenders from military service was made in consultation with generals who know more than I do about what is best for our military," said Marshall, referring to Trump's tweet that he made his decision after consulting generals and military experts.
It is unclear, however, whom in the military Trump had consulted.
His defense secretary, Jim Mattis, ordered a review of a plan to accept transgender troops that was due in December. Brad Carson, a former congressman who worked on transgender policy deliberations during the Obama administration, said no member of the Joint Chiefs of Staff favored a full ban.