D.C. Council member Trayon White Sr. (D-Ward 8) says that he will run for mayor of Washington.

White, who first floated his plans publicly Wednesday in Instagram comments reported by Washington City Paper and then confirmed in messages to a Washington Post reporter, would be the second council member to join the race. Robert C. White Jr. (D-At Large) filed paperwork to run on Wednesday morning.

“Yes I’m running,” Trayon White Sr. told The Post in an Instagram message.

Both men would likely run in next year’s Democratic primary as left-leaning alternatives to Mayor Muriel E. Bowser, a more moderate Democrat expected to seek a third term leading the city.

White, who has represented the city’s poorest ward on the council since 2017, has used his position to be a blend of legislator, activist and community organizer. It’s common to see White, 37, distributing food or school supplies, attending a vigil or live-streaming a video of police behavior in Ward 8. His ground-level involvement has inspired enthusiastic support among his constituents, even when he has been criticized for embracing conspiracy theories.

Tom Lindenfeld, an adviser and friend of White, and former campaign consultant for Bowser, said White “is being encouraged to run by people across the city.”

“They think his advocacy and voice for people who have been left out is needed, and on that basis, I think he’s likely to accept that challenge and pursue a candidacy,” said Lindenfeld, who advised White in his 2020 council reelection campaign.

White has not yet filed paperwork to run.

A Southeast D.C. native and graduate of Ballou Senior High School, White has long advocated for residents east of the Anacostia River. As a council member, he emphasizes the need for resources in his community that are readily available in more affluent areas — particularly in the areas of housing, youth services and education.

He has made gun violence his top priority in office, frequently calling attention to the crimes that disproportionately plague some areas of the city, including the ward he represents. White regularly meets with victims’ families after shootings, and has spoken out about the personal toll that gun violence has taken on his own family and friends.

Earlier this year, he called on the District to treat gun violence as a public health emergency. Bowser heeded his suggestion within weeks; when she announced a new “whole-government” approach to invest millions more dollars in gun violence prevention, White was by her side.

A graduate of the University of Maryland Eastern Shore who is pursuing a law degree while serving on the council, White is an occasional proponent of novel ideas. He proposed a bill shortly after George Floyd’s murder in Minneapolis police custody that would have required D.C. police to take any distressed person who says the words “I can’t breathe” to a hospital for a medical check. (The bill never advanced; other council members praised the intent but questioned the practicality of the measure.)

White won his first election when, as a young father in 2011, he ran to fill a vacancy on the D.C. Board of Education. Former mayor Marion Barry, who represented Ward 8 on the council after serving four terms as D.C. mayor, supported him when he ran and won a full term the following year.

White then worked for Attorney General Karl A. Racine (D), before running for the council in 2015 in a special election to fill Barry’s seat after his death.

He lost by just 79 votes to LaRuby May, the candidate Bowser supported, and then defeated May resoundingly in a rematch the next year in which supporters frequently compared him to Barry. He won a second full term last year, far outpacing three candidates who challenged him in the Democratic primary.

In 2018, White sparked an uproar that has tinged his reputation in some corners of the city ever since: He posted a video saying that a snowstorm in D.C. came from “the Rothschilds controlling the climate to create natural disasters they can pay for to own the cities,” naming a Jewish family who has been the focus of many antisemitic conspiracy theories.

Amid the ensuing outcry, Jewish leaders invited him to a bagel breakfast and a tour of the U.S. Holocaust Memorial Museum; he left the 90-minute tour halfway through. His $500 donation from his constituent services fund to a Nation of Islam convention where founder Louis Farrakhan made remarks criticizing Jews was reported at the same time.

White initially said that he was “under attack” and “not backing down,” but later repaid his constituent services fund for the donation, which the D.C. Office of Campaign Finance said was an “inappropriate” use of the fund.

He has also occasionally echoed the language of conspiracy theorists who cast doubt on the safety of vaccines. He was the only member to vote against a coronavirus vaccination requirement for the council and its staff, saying that he opposes “the government mandating what people do with their bodies.” He was also the most vocal opponent of a law passed last year to allow teenagers to consent to routine childhood vaccinations on their own without parental approval if a doctor deems them competent to make the choice for themselves, asserting parents had a right to direct the care of their children.

White said last week that he is fully vaccinated against the coronavirus, and at the council meeting where he voted against requiring staff to be vaccinated, he waved a card that he said was his own vaccine card.

White appears to have first announced his intention to run for mayor in a comment on an Instagram post made by the popular Instagram account Washingtonian Probs about Robert White’s announcement. “I’m running,” Trayon White Sr. responded to a commenter who said he should be mayor.

Wednesday afternoon, he responded to other Instagram comments with similar affirmations that he is planning a run, and reposted more than 30 people’s posts celebrating his newly announced candidacy in an Instagram story.

White confirmed his future mayoral bid in messages to The Post but did not elaborate on any other details of a potential campaign.