Gov. Andrew Cuomo on Wednesday called the effort to overhaul mass transit systems in New York City the toughest issue he’s dealing with in the state budget this year.

Cuomo in a radio interview with The Brian Lehrer Show on WNYC demurred when asked if the votes in the Legislature are available for the provision, part of the broader $175 billion budget proposal, are there for it to pass.

“It is a tough issue, but I’m cautiously optimistic,” Cuomo said. “It’s the single toughest issue we have on the agenda.”

The effort is meant to raise more funds for New York City’s trouble subway system through congestion pricing by tolling vehicles in Manhattan south of 61st Street, a property tax surcharge on high-end second homes and collecting sales tax on out-of-state Internet purchases.

But the issue of tolling, known as congestion pricing, has struggled to gain traction over the last decade in Albany and state lawmakers are once again hesitant to approve it.

“Congestion pricing is the greatest opportunity we have had, we’ve talked about it for 20 years,” Cuomo said. “It is the smartest idea I think for urban development.”