Three Massachusetts Democrats to compete in gubernatorial primary
The winner will run against a Republican in November to succeed Democrat Deval Patrick, who is stepping down after two terms running the liberal-leaning state.
Coakley, who lost a 2010 U.S. Senate race to Republican Scott Brown in a major upset, holds a 49 percent to 14 percent lead over Grossman in a Boston Globe poll of state voters conducted in early June.
But she is less popular with party insiders who were voting at Saturday's convention, owing to lingering disappointment with her campaign effort against Brown for theSenate seat that opened up when popular, long-serving Democrat Ted Kennedy died.
Coakley acknowledged those sentiments in a Saturday speech to delegates that was broadcast on New England Cable News.
"The 2010 Senate election was very painful for a lot of people in this room," she said. "I understand how much of your heart and soul was in that race. Mine too."
Coakley came in second on Saturday with 23.3 percent of votes cast, the Boston Globe reported, well behind Grossman's 35.2 percent. Berwick trailed with 22.1 percent.
Grossman has championed liberal issues including raising the minimum wage and told delegates: "I want to be known as the progressive job creator."
While Democrats outnumber Republicans about 3-to-1 among registered voters, the state has elected four Republicans as governor since 1990, including 2012 presidential nominee Mitt Romney.