Writing on Twitter after the result was announced, she told her supporters: “We did it. We won the general election. Thank you, thank you, thank you.
“I hope tonight shows an LGBTQ kid that our democracy is big enough for them, too.”
Ms McBride earned herself something of a national profile when she addressed the Democratic National Convention in 2016, with a speech in which she celebrated the chance to elect LGBT+ candidates across the country.
“Will we be a nation where there’s only one way to love, one way to look, one way to live?” she asked the crowd. “Or will we be a nation where everyone has the freedom to live openly and equally; a nation that’s stronger together?”
Ms McBride’s district is a solidly Democratic one, while Delaware at large is a reliably Democratic state (as well as being home to Joe Biden).
Three years before Ms McBride’s victory, transgender Democrat Danica Roem became the US’s first openly trans elected official when she won election to the Virginia House of Delegates. Several other trans candidates are standing at state level this year.