Patrick had been viewed as a prospective 2020 candidate after ramping up his political activity in 2018 by traveling to a handful of races across the country. Close advisers to Patrick, including political consultant Doug Rubin, launched a political action committee that year, the Reason to Believe PAC, aimed at "promoting Governor Patrick’s positive vision for Democrats to rally around in 2018."

But he ruled out a White House run nearly a year ago, announcing in December that the "cruelty" of the process would have a negative impact on him and his family.

The Reason to Believe PAC folded earlier this year, and Rubin is consulting for billionaire Tom Steyer's presidential run.

Patrick, who served as governor of Massachusetts from 2007 to 2015, would become the fourth politician from Massachusetts to run for president this election cycle. Sen. Elizabeth Warren is among the candidates leading the field, and Rep. Seth Moulton (D-Mass.) briefly pursued a bid before dropping out in August. Former Gov. Bill Weld is running in the Republican primary.

Patrick was also among the Democrats who met with former President Barack Obama at the outset of the 2020 cycle, and Obama's inner circle had encouraged him to run.

After his governorship, Patrick went to work in the private sector at Bain Capital. But in recent months, Patrick has been burnishing his political profile. The former governor became a CBS political analyst and joined the advisory board of Higher Ground Labs, an accelerator and venture capital firm that supports progressive tech tools.