Rauner on Tuesday announced he raised more than $9 million in the first three months of the year.
Quinn says he raised $5 million in the first quarter, much of it from labor unions. He spent little of it defeat a little-known challenger in last month's Democratic primary. Quinn finished the quarter with $8.8 million in his campaign fund.
Rauner defeated three rivals in the March primary. His fundraising total includes millions of his own money. But the wealthy businessman from Winnetka says he's received more than 6,900 individual donations since he announced his bid last year.
The campaign says Rauner carried more than $1.3 million into the second quarter.