Illinois Attorney General Lisa Madigan said she will not seek the Democratic nomination for governor.
Madigan said Monday she will instead seek a fourth term for her current office.
In a statement, she said deciding her political future has not been easy.
In a nod to Quinn's poor favorability in polls -- and frequent criticism from within his own ranks -- Madigan wrote she considered running because "of the need for effective management from that office and the frustration so many of us feel about the current lack of progress on critical issues facing Illinois."
But in the end, it came down to her father, who is longtime Speaker of the Illinois House, Mike Madigan.
The Attorney General said that with her father planning to continue in that office, she will not run for governor.
She wrote that the "state would not be well served by having a Governor and Speaker of the House from the same family."
Speaker Madigan has been under scrutiny since revelations last week that he allegedly tried using his political clout to force the suburban rail agency Metra to give a raise to a person who’s contributed to his campaign and to his daughter's campaign.
Despite Lisa Madigan’s announcement, Governor Quinn still faces a challenge from within his own party from Bill Daley.
In addition, four Republicans are seeking the GOP nomination. The latest to join the race is Kirk Dillard, who made his announcement Monday.
Dillard narrowly lost the primary to State Senator Bill Brady in 2010.
Dillard, Brady, State Treasurer Dan Rutherford, and venture capitalist Bruce Rauner have all announced bids for the GOP nomination for governor.