SEN. SONIA CHANG-DIAZ, a hard-charging liberal who has championed issues ranging from education funding to criminal justice reform in her 13 years in the Legislature, declared her run for governor on Wednesday, vowing to bring an activist approach to tackle inequality and other challenges facing Massachusetts. 

“Voters didn’t send me to the state Senate to wait,” Chang-Diaz says in a kickoff video announcing her candidacy that emphasizes her impatience with change and willingness to buck the establishment. “Beacon Hill has learned three things about me: I speak up, I organize, and I win,” she says. 

A Latina who is the lone woman of color in the Senate, the 43-year-old Jamaica Plain lawmaker becomes the third Democrat in the 2022 race, joining former state senator Ben Downing and Harvard professor Danielle Allen. 

Chang-Diaz announced in late March that she was “seriously considering” a run for governor. 

Chang-Diaz was a leading Senate proponent of the police reform bill passed in 2020, and she was a forceful advocate for the criminal justice reform bill signed by Gov. Charlie Baker in 2018. In January 2018, Chang-Diaz delivered a fiery speech at a Martin Luther King Day breakfast attended by Baker and other top state leaders where she called out officials for years of delay in reforming the state’s mandatory-minimum sentencing laws and making other changes included in the bill passed later that year. 

Chang-Diaz was a leading proponent of the effort to rewrite the state’s education funding formula, a years-long effort that culminated with the 2019 passage of the Student Opportunity Act. She had served as co-chair of the education committee when efforts to pass a bill came up short at the end of the 2018 legislative session. In 2019, Senate President Karen Spilka replaced her as the Senate chair of the committee, but she continued her involvement in the effort.

“Those wins didn’t come easy,” she says in her kickoff video about the criminal justice reform and education funding measures. “Beacon Hill insiders dragged their feet every step of the way.” 

Chang-Diaz has been a harsh critic of Gov. Charlie Baker’s policies on everything from criminal justice issues to his handling of the pandemic. 

Voicing strong support for the so-called millionaires tax on high earners that will appear on next year’s state ballot, she declared in her video that “our state is at a turning point and we face a choice: do we go back to business as usual or do we run toward problems with the urgency and determination to solve them.” 

Chang-Diaz won her Senate seat after beating longtime incumbent Dianne Wilkerson in a 2008 Democratic primary race.

Chang-Diaz grew up in Newton. Her mother worked as a social worker and her father, an immigrant from Costa Rica, became NASA’s first Latino astronaut.   

She has stops planned across the state on her first day in the race, starting with a morning meeting in Springfield with leaders of color, a mid-day stop in Worcester to meet with small business owners and striking nurses at St. Vincent’s Hospital, and a formal kickoff announcement at 4:30 pm at English High School in Jamaica Plain. 

Along with the three declared Democrats now in the race for governor, Attorney General Maura Healey is widely believed to be weighing entering the Democratic primary. 

Baker, a second-term Republican, has yet to announce whether he will run for a third term.