Inside the Audition for Democrats’ Next Crusading Attorney General

“It’s the people’s attorney,” said Marie St. Fleur, a former assistant attorney general in Massachusetts who is close to Campbell. “That’s who we are.”

This weekend, the three candidates will face their first test when delegates to the Democratic Party’s state convention will vote to decide who receives the party’s endorsement. Any candidate who does not reach 15 percent support among delegates will not make the primary ballot.

Palfrey and Liss-Riordan have attacked Campbell for refusing to disavow a super PAC, Better Boston, that spent $1.6 million in support of her mayoral run. Palfrey has said the donations could create “a conflict of interest” if Campbell becomes attorney general. Both have pushed Campbell to sign the People’s Pledge, an agreement to reject corporate donations that was popularized by Senator Elizabeth Warren. She has refused.

“That’s probably because they realize that Campbell has the early lead,” said David Paleologos, the director of the Suffolk University Political Research Center, who has seen private polling in the race that heavily favors Campbell.

Better Boston has not spent any money so far in the attorney general’s race, though it has not shut down, either. Its donors include Reed Hastings, a chief executive of Netflix, who chipped in $250,000; Andrew Balson, a former managing director at Bain Capital, who likewise gave $250,000; and Jim Walton, an heir to the Walmart dynasty, who donated $45,000. Sonia Alleyne, a former bank executive listed as the chairwoman of the group, did not respond to emails.

Critics of corporate money in politics say the super PAC’s looming presence in the race is unprecedented, and has the potential to be corrupting even if the group is not currently active.

“I’m not aware of a super PAC spending in an attorney general’s race in Massachusetts, ever,” said Jeff Clements, the president of American Promise, a nonprofit group that supports tightening campaign finance laws, and a former chief of the public law enforcement bureau in the Massachusetts attorney general’s office. “When that kind of raw power can be used to decide who can be the chief law enforcement officer of a state, that’s a big deal.”