Melissa Mark-Viverito, who was the first person of color to serve as New York City Council speaker, announced her candidacy Wednesday to replace outgoing Rep. José Serrano of the Bronx.

Mark-Viverito, originally from Puerto Rico, is the sixth Democrat to announce an interest in succeeding Serrano, who is also of Puerto Rican descent and represented the predominantly Latino district, one of the nation's poorest, for 16 terms.

Serrano, who has Parkinson’s disease, announced in March that he would not re-election in 2020.

“After my diagnosis, I initially planned to continue my work representing the people of the South Bronx far into the future — a responsibility that brings me great joy," he said in a statement. "Although this disease has not affected my work in Congress, over the last few months I’ve come to the realization that Parkinson’s will eventually take a toll, and that I cannot predict its rate of advancement."

State Assemblyman Michael Blake and New York City Councilmen Ritchie Torres and Ruben Díaz Sr. are among those joining Viverito in seeking to succeed Serrano. Viverito is currently the interim president of the Latino Victory Fund, a political action committee that aims to get more Latinos in public office.

"I served as speaker of the NYC Council for five years, where I’ve fought for women, immigrants, LGBTQ communities, and black and brown New Yorkers that have historically been ignored by our government," said Mark-Viverito in her announcement.

As a way to try to stand out in the crowded field, Viverito painted herself as the early leader of the progressive wave sweeping Democratic politics in New York in an interview with The City, a local independent and nonprofit news outlet.

"At a time when the norm was being pragmatic, I was being cutting-edge, ahead of the curve, and putting forward progressive policies that set us, as New York City, on a path for us to be a model for others,” she told The City.

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