NEW YORK — “LGBT” has become a household term amid sweeping advances for gay rights, and yet the “B” sometimes seems like an awkward fit. The sudden advent of America’s first openly bisexual governor may provide a chance to ease the awkwardness and broaden understanding of the bi community.

Kate Brown, Oregon’s secretary of state, is in line to replace Democratic Gov. John Kitzhaber when he steps down Wednesday amid an ethics scandal. Brown, serving her second term after many years in the legislature, lives in Portland with her husband and two stepchildren and has been open throughout her political career about being bisexual.

Her progress has been followed closely by bisexual activists across the country, including Ellyn Ruthstrom, who now serves on the board of Boston-based Bisexual Resource Center after 10 years as its president.

“There are so few bi political leaders out there, so we pay attention to them,” said Ruthstrom, citing U.S. Rep. Kyrsten Sinema of Arizona as the other prominent example.

Beyond elective politics, the bi community continues to struggle to establish its appropriate place in the broader civil rights campaigns being waged on behalf of lesbians, gays and transgender people.

Within that movement, there was widespread animosity toward bisexuals a couple of decades ago, Ruthstrom said. “Now it’s not as overt, but there are still issues.”

She cited a phenomenon known as “bi-erasure” — in which bisexuals are not mentioned in speeches, press releases and news reports that refer to the LGT groups.

Ruthstrom said she and her allies have been lobbying major LGBT-rights groups to be fully inclusive of the bisexual community’s issues. “They’re missing an opportunity to engage,” she said, citing research indicating that bisexuals make up about half of the total LGBT population.

Gary Gates, a demographer at the UCLA School of Law’s Williams Institute, estimated in 2011 that about 1.8 percent of the adult population, or a little more than 4 million Americans, identifies as bisexual — slightly more than the number identifying as gay or lesbian.

However, Ruthstrom said a majority of bisexuals remain wary of disclosing their sexual orientation, except perhaps to a few close acquaintances, and suffer high rates of depression. A study released by the U.S. Centers for Disease Control and Prevention two years ago said bisexual women reported a far higher rate of rape, violence and stalking by an intimate partner than either lesbians or heterosexual women.

A vice president of one of the largest LGBT-rights groups, Fred Sainz of the Human Rights Campaign, said bisexuals may in some respects face greater challenges than gays and lesbians.

“To the extent that they’re out, they may well be more so the victims of scorn because they get it from both gay and straight people,” Sainz said. “Gays want them to make a choice, and straights consider them gay, so in many ways they face increased amounts of stigma and discrimination.”

The Human Rights Campaign’s legal director, Sarah Warbelow, who is bisexual, said one of the biggest challenges for the bi community is a lack of public understanding of their social lives.

“On one hand, there’s assumption that bi people are never happy in any relationship and need to have multiple partners,” she said. “On the other hand, you’ve got people who say it’s not real — it’s an in-between existence until you figure out who you really are when you grow up.”

Brown’s pathway to the governor’s office opened up as the Human Rights Campaign was convening a conference in Portland devoted to supporting LGBT youth.

“Kate Brown is an incredible role model for bisexual youth, many of whom are grappling with the same issues that Brown dealt with when she came out in the ‘90s — including feelings of not being understood by family or by their gay peers,” said Ellen Kahn, an HRC official helping organize the conference.

Efforts to increase understanding have persisted over many years,

In 2009, for example, activists convened a “Putting the ‘B’ in LGBT” summit in New York City. In September 2013, the White House convened a meeting with more than 30 bisexual activists — the first such gathering of its kind.

Kate Brown, after entering politics in 1991 as a member of Oregon’s House of Representatives, wrote a brief essay for “Out and Elected in the USA” about what it was like for her to come out as bisexual to her parents, her gay and straight friends, and her fellow lawmakers.

Her parents’ response: “It would be much easier for us if you were a lesbian.” Some gay friends called her “half queer.”

“Some days I feel like I have a foot in both worlds, yet never really belonging to either,” Brown concluded.