Shannon Liss-Riordan, a workers' rights lawyer, announced her intention Monday to challenge the one-term senator for the Democratic nomination.
Liss-Riordan made the announcement in a video and email to supporters and Democratic activists.
Liss-Riordan, 49, said she has spent her career representing workers who have been taken advantage of by their employers, including servers whose bosses were taking their tips. She's a graduate of Harvard Law School and Harvard College.
In her video, Liss-Riordan doesn't mention Markey by name, but instead seeks to tap into the #MeToo movement and appeal to a Democratic Party that is increasingly supportive of more diverse candidates.
She mentions both Anita Hill, who accused then-Supreme Court nominee Clarence Thomas of sexual harassment in 1991, and Christine Blasey Ford, who accused then-Supreme Court nominee Brett Kavanaugh last year of sexually assaulting her when they were teenagers decades ago. Both men were later confirmed to the court.
"It was as if nothing had changed," Liss-Riordan said in the video. "This country is stuck because of the cycle of Washington politics. Washington needs a fresh voice willing to break that cycle."
Hours after Liss-Riordan's announcement, Markey issued a press release announcing key political positions in his campaign, ahead of a formal launch.
Markey said the country's democracy is under assault every day by President Donald Trump and what he called Trump's "hate, division, and inequality."
"We are all called to stand up in the fight for the future of our country," Markey said. "I want to continue helping to lead that resistance in the United States Senate armed with an agenda of jobs and justice and a deep commitment to the freedoms born in the Commonwealth."
Markey is considered potentially vulnerable at a time when an increasing number of women are being elected to Congress, particularly among Democrats. Just last year, Ayanna Pressley defeated longtime incumbent U.S. Rep. Michael Capuano in the Democratic primary and went on to become Massachusetts' first black woman elected to the U.S. House.
But there are differences. Pressley was a well-known Boston city councilor in a relatively compact, largely urban district, while Liss-Riordan is less well-known and will have to run statewide against a candidate with deep political roots.
And the 72-year-old Markey - who spent decades in the U.S. House before winning Democrat John Kerry's former Senate seat in 2013 - has worked to tap into a new political energy on Capitol Hill.
Earlier this year, Markey teamed up with freshman Democratic Rep. Alexandria Ocasio-Cortez of New York to launch the Green New Deal - a sweeping plan that aims to transform the U.S. economy to combat climate change and create thousands of jobs in renewable energy.
Markey raised more than $950,000 during the first three months of the year, bringing his campaign war chest to more than $3.5 million.
Nearly 75% of Markey's contributions during the first quarter of 2019 came from individual donors, with the rest coming from other sources like political action committees, according to reports filed with the Federal Election Commission.
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