In the fall of 2015, the thought of running for office was not even in the “realm of possibility” for Christine Hallquist, she said in an interview with The Washington Post.

Hallquist, then CEO of Vermont Electric Cooperative, was in the midst of coming out professionally as a woman to her employees and worried they might not accept her. The company’s website still indicated that the firm was led by a man, Vermont alternative weekly Seven Days reported at the time. Her emails were still signed by her former name.

“Here I am, the transgender CEO of one of the most macho businesses,” Hallquist told Seven Days.

Just three years later, Hallquist could become the country’s first transgender governor.

On Tuesday night, Hallquist won her Democratic primary race in Vermont, becoming the first openly transgender candidate nominated for governor by a major party in the United States.

“Tonight we made history,” Hallquist, 62, told supporters during a victory speech. “I’m so honored to be part of this historical moment.”

Hallquist, a first-time candidate, won in a crowded field of four Democrats, including an environmental activist, a dance festival organizer and a 14-year-old boy. She is part of a progressive wave of political novices, women and LGBTQ candidates running in this year’s midterm elections, many of them galvanized by the election and behavior of President Trump. Transgender women in particular are running for office in record numbers this year, according to the Victory Fund, which helps elect LGBTQ candidates.

But Hallquist faces a steep path to the governor’s office. Republican Gov. Phil Scott remains popular in the state, even among Democrats. He has signaled a willingness to work with Democrats on issues such as gun control legislation, which he signed in April. He also has history on his side: No incumbent governor has been unseated in Vermont since 1962.

Hallquist points to Scott’s declining approval numbers in recent months and argues he “is not doing us any favors in these areas that we all support.” Like many progressives running in this cycle, Hallquist supports Medicare-for-all, the health-care policy championed by fellow Vermonter Sen. Bernie Sanders (I). If elected, she also wants to combat climate change, expand rural Vermont’s infrastructure and improve equality in the state’s public education system.

“That message has resonated in every small town in Vermont,” Hallquist said during her victory speech, “because it’s the right message and it’s the just message.”

Growing up in Upstate New York and going to Catholic school, Hallquist always felt like she was a girl, she told Seven Days. She took up competitive running and skiing but secretly collected women’s clothes in her closet. She moved to Vermont in 1976, and pursued a career in engineering. She joined Vermont Electric Cooperative, which provides power to parts of the state, in 1998 and became CEO in 2005.

She came out as a woman to her wife, Pat, early in their marriage, and opened up to their three children about eight years ago. But it was not until 2015, when she was CEO of Vermont Electric Cooperative, that she started publicly identifying as a woman. Local news outlets documented her transition, and she drew national attention as a pioneering example of a business CEO transitioning while in office.

At an energy conference in October 2015, she reintroduced herself to acquaintances in the industry. “You probably remember me as David,” Hallquist said, shaking hands with an environmental activist at the conference, according to Seven Days.

She feared what kind of reactions she would get from members of her board but said she was fully supported across the company and industry.

“When you transition it’s not about what others think,” she said in an interview with The Post early Wednesday morning. “It’s about coming to terms with yourself.”

She continued to serve as CEO of the co-op until earlier this year, when she resigned to run for office. While she touts the company’s “carbon free” track record and wants to make Vermont almost entirely reliant on renewable energy, some have raised questions about how far her commitment to renewable energy went while at the co-op.

It was not until January of this year that Hallquist decided she wanted to run for governor. She was at a Women’s March in Vermont, watching four young Muslim women talk about the challenges they faced. Hallquist started crying, she said.

She realized that “our lovely cocoon in Vermont has been pierced by the hatred coming out of Washington,” she told The Post. “Coming from a marginalized community myself, that really hit me hard.”

Her victory Tuesday night, she said, is a testament to Vermont, a historically progressive state that was the first to recognize same-sex unions.

“Vermonters have always been the first in civil rights,” she said. “They certainly looked beyond the fact that I’m transgender and looked at the issues.”

Hallquist said she knows her team will have to “double down” leading up to November. She had raised about $132,000 by mid-July, according to the Associated Press, but said this week she was giving back about $16,000 in corporate donations. Scott had raised about $177,000 by mid-July, but a PAC backed by the Republican Governors Association had raised more than $1 million to support Scott, the AP reported.

“We’ve got to make up for the dollar difference in terms of our scrappiness and our commitment,” Hallquist told The Post.

She commended the many women and members of the LGBTQ community who have stepped up and run for office in this election cycle.

“This is a national movement and we’re part of that movement,” she said in her victory speech. “In the physics world we have this saying . . . for every action there’s an equal and opposite reaction. This is a reaction to 2016.”

About 200 LGBTQ candidates are running for state or federal office in this election cycle, according to the Victory Fund. Other openly transgender candidates include former military intelligence officer Alexandra Chandler, Massachusetts’s first openly transgender candidate for Congress, and Kim Coco Iwamoto, who is vying to become Hawaii’s first transgender lieutenant governor.

According to the Victory Fund, 13 openly transgender people are currently serving in some type of elected office in the United States. Among them is Danica Roem, a Democrat who last year unseated one of Virginia’s most socially conservative state lawmakers, Del. Robert G. Marshall, a 13-term incumbent who called himself Virginia’s “chief homophobe.”

Roem on Tuesday night took to Twitter to congratulate Hallquist on her victory. “If anyone tells you the Republican incumbent is too entrenched for you to defeat in the general election . . . yeah, about that,” Roem said. “Go win.”

Fellow political newcomer Alexandria Ocasio-Cortez, who this year unexpectedly defeated a top Democratic incumbent in the primary for New York’s 14th Congressional District, also tweeted her support for Hallquist, calling it an “incredible and groundbreaking victory.”

Sanders also commended Hallquist’s win.

Victory Fund called her primary success a “defining moment in the movement for trans equality.”

“Many thought it unthinkable a viable trans gubernatorial candidate like Christine would emerge so soon,” the group said in a statement. “Yet Vermont voters chose Christine not because of her gender identity, but because she is an open and authentic candidate with a long history of service to the state, and who speaks to the issues most important to voters.”

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