His challenger Bill Daley did not attend the meeting of township and ward committeemen.
Voters from Cook County usually make up two-thirds of ballots cast statewide in a Democratic primary. So Friday's vote would appear to be a major win for Pat Quinn and another bump in the road for challenger Bill Daley.
As the governor worked the room before the meeting, he knew the Cook County Democratic endorsement was in the bag.
Quinn seemed not worried about another contested primary in 2014.
"Every campaign is tough," he said. "But I've been proven in our state, every part of our state."
"One candidate appeared and that candidate was the incumbent Governor. So I don't think the outcome is surprising," said 4th Ward Committeewoman Toni Preckwinkle.
Bill Daley, Quinn's only announced primary opponent, conceded the endorsement and chose not to appear before the committee.
"Well, it's his choice but I think that 99 percent of life is showing up," said Quinn.
In a statement, the Daley campaign wrote the same committee had backed Rod Blagojevich in 2006 as well as the current governor in 2010, "?no matter how failed Governor Quinn's record is."
"If you want to become an active participant in this race, you have to be all over the place," said 27th Ward Committeeman Jesse White.
"I don't know what his motive was or why he's not here," said 50th Ward Committeeman Senator Ira Silverstein. "There might be a strategy that many of us don't know."
Daley was given a lukewarm, polite reception at Wednesday's state Democratic Party breakfast in Springfield. Minutes later, Governor Quinn was applauded by supporters in the audience. Daley so far has not opened any Chicago or downstate offices.
"He's going to bring his case to the people of the state," said 11th Ward Committeeman John Daley.
John Daley, the Cook County Commissioner, was one of only three Democratic committee members not to support Quinn. He says his younger brother remains a viable candidate as he downplayed the role of his fellow democratic bosses.
"The voters of this state will decide who is going to be the next governor and I believe Bill will be a strong candidate bringing his case to the people of this state and he will campaign throughout the state," John Daley said.
Also absent from the meeting was Democratic State Senator Kwame Raoul who says he's considering a run for governor. Some committee members favored holding off on an endorsement until the field was complete.
But that idea gained no traction as the cook democrats gave Pat Quinn their nod.