Conservative lawmakers hailed the change as a way to avoid what they said could be a potentially awkward situation. But one of the longest-serving House Democrats called the decision "shameful" and said lawmakers "ought to be big enough to get over these hang-ups we have."
Cox's office said he had been considering the change since shortly after he was chosen as the party's designee for speaker, a title he would assume if the GOP retains control over the House after three close races are decided.
His statement to The Washington Post on Tuesday came in response to questions about how Del.-elect Danica Roem (D) — who in a campaign ad spoke about the power of being referred to as "the gentlewoman" from Prince William County — would be referred to when the legislative session begins in January.
"All members will be afforded the same respect and courtesy that this nearly 400-year-old institution commands," Cox spokesman Parker Slaybaugh said. "Speaker-designee Cox believes the 'gentlelady' and 'gentleman' terminology is outdated, and that referring to everyone as 'delegate' is more timely and appropriate."
Political analysts said Virginia Republicans have been caught in a bind since Roem defeated conservative Del. Robert G. Marshall (R-Prince William), becoming one of the first openly transgender state lawmakers in the country.
Marshall repeatedly referred to Roem as male during the campaign, while a flier paid for by the Republican Party of Virginia that also used male pronouns accused her of trumpeting her transgender identity to win more votes.
"They're trying in some way to thread a needle with their own base," said Bob Holsworth, a former Virginia Commonwealth University political-science professor. "They're willing to change the tradition in this sense before they will explicitly acknowledge Danica Roem as a woman."
Roem said she thinks it's remarkable that Republicans are willing to upend years of tradition because of her victory. But, she added, in the end it doesn't matter much as long as other transgender people know that it's possible to win elected office.
"What matters the most is that I'm there," she said. "What matters the most to the people of the 13th District is that the woman they elected to serve them will be working on their behalf. I will be the delegate from Prince William, and I will conduct myself as the gentlewoman from Prince William while I'm in Richmond and in any other official capacity in which I serve."
The formal references to "gentleman" and later, "gentlewoman" in the General Assembly have long been a way to impose civility in what can be raucous debates, historians said. The Virginia senate does not use similar honorifics.
Del. Kenneth R. Plum (D-Fairfax), a 36-year lawmaker, said he was "really disappointed" to hear of the change.
"If Danica Roem had not won the election we would still be doing the same thing we have done for 400 years," Plum said, "calling each other gentleman or gentlelady. It's unfortunate that we, in effect, have to single out her election, as unique as it is."
Republicans said that it is better to leave gender references behind. "There are always changes going on," said state Sen. Richard Black (R-Loudoun,) one of the staunchest conservatives in Richmond. "We sometimes refer to women by the term 'Ms.,' which didn't exist until some years ago. It used to be 'Miss' or 'Mrs.' Then, it was 'Ms.' "
Travis Witt, the pastor of Gilboa Christian Church in rural Mineral, Va., and the former chairman of the Virginia Tea Party Patriots Federation, also applauded the gender-neutral approach.
"It's one of those things that we're going to be forced to deal with," said Witt, who was a vocal supporter of a failed bill by Marshall this year that would have restricted where transgender people could use the bathroom inside government buildings. "It is much safer to use a nebulous, neutral term."
Since her underdog victory, Roem has tried to strike a balance between capitalizing on the national attention her win has gotten and delving into the more mundane aspects of her new office.
On Sunday, she walked the red carpet at the American Music Awards in Los Angeles with pop singer Demi Levato, who said she appreciated and wanted to promote Roem's respect-for-all message. She flew back to Virginia immediately after the awards show to make an early-morning meeting on teacher pay and class sizes with the Prince William County School Board.
Roem also has had a tutorial on General Assembly parliamentary procedures and met with other elected officials and advocacy groups about legislative priorities for the session that begins in January.
"It's fair to say that your average Virginia delegate lives a life of quiet and, at most, local fame," said Stephen J. Farnsworth, a political-science professor at the University of Mary Washington in Fredericksburg. "So, if one has the chance to walk the red carpet, that could be very useful for building a national profile for causes of interest as well as raising money for a future campaign. But I suspect the voters of Prince William County will expect, particularly during the legislative session, that delegates stick to business."
Roem said she was initially reluctant to engage too much in the calls for media appearances and other invites that have come her way since her victory.
She had planned to emulate Hillary Clinton, who in 2001 overcame skepticism about her ability to serve in the U.S. Senate by diving deep into the minutiae of governing.
"That's why she was a successful senator," Roem said. "When you enter office with a high profile, you need to show people: Hey, you're serious about the job you're elected to do."
But the opportunity to help Lovato promote an anti-bullying message seemed too good to pass up. Roem said she also thinks that a national platform could make it easier to advocate for the issues she cares about.
Besides alleviating Route 28 traffic, she wants to increase state education funding, improve state government transparency and prohibit health insurance companies from denying coverage for doctor-prescribed treatment received by transgender patients.
With control over the House of Delegates still uncertain, Roem said she had also hoped to earn respect from Republican colleagues.
Quentin Kidd, director of the Wason Center for Public Policy at Christopher Newport University, said it's uncertain whether Roem can win that respect.
But the era of "gendered terms" in the General Assembly is probably over, Kidd said, adding that he doesn't see that as necessarily bad.
"The irony is that may take the first transgender person elected to a state office anywhere in the country to get this to happen," he said.
Jenna Portnoy contributed to this report.
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