Denver Mayor Michael Hancock speaks in support of a ballot measure that would create a city scholarship fund, during a rally at Sunken Gardens Park on Thursday, Sept. 24, 2015. 

(Vic Vela/For CPR News)

Organizers of an effort to create a college fund for Denver students held a campaign kick-off rally Thursday.

A ballot measure will ask Denver voters to approve a sales tax hike to fund the program. It amounts to about a penny on every $10 purchase.

Critics say it's not the city's job to provide education funding. But Denver Mayor Michael Hancock said he heard similar arguments about Denver's popular preschool tuition assistance program. And he said partisan battles at the state level have done little to make college more affordable.

“You recognize that this is an uphill battle and at some point, as we have done with our schools here in Denver, you know what, it's not just about the state it's about the city," Hancock said.

If approved, the sales tax increase is expected to generate $10 million a year for scholarships.