Zohran Mamdani's promise to make buses fast and free during his tenure as New York City mayor has hit a bit of a speed bump after Gov. Kathy Hochul cast doubt about the plan over the weekend.

"I cannot set forth a plan right now that takes money out of a system that relies on the fares of the buses and the subways," Hochul told NY-1 while in Puerto Rico. "But can we find a path to make it more affordable for people who need help? Of course we can."

Mamdani stayed on track Monday, touting his vision for the city.

"The success of our administration will not only be measured in the questions of the hallmark three points of our agenda, but also in the questions of whether public goods are functioning effectively across the city," the mayor-elect said.

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Odds stacked against Mamdani's plan, political expert says

J.C. Polanco, a professor at the University of Mount Saint Vincent in the Bronx, says Mamdani's proposal requires clearing a series of hurdles, including safety concerns, bus capacity, and cost.

"He's going to need the support of the MTA and the state Legislature. Really, the governor," Polanco said. "Here in New York City now, we have about a $452 million shortfall with the MTA. It's one of the major reasons we have congestion pricing to make ends meet."

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Mamdani estimates the cost of free and fast buses will total about $800 million per year. Back in September, he told CBS News New York the loss in fare revenue can, in part, be covered by increasing the corporate tax rate to 11.5%, and by implementing a 2% tax rate for New Yorkers earning more than $1 million.

"Does [Hochul] raise taxes? She has already said no to that. And would you raise taxes? Would anybody raise taxes in the middle of an election? I don't think so," Polanco said.

"I think it's going to be great for people"  

The governor's office and the MTA said they will continue to have conversations with the mayor-elect about his fare-free plan.

"There was a lot of thoughtful discussion during the campaign about the importance of mass transit, and we look forward to working closely with Mayor-elect Mamdani and his administration," MTA CEO Janno Lieber said in a statement.

Riders that spoke to CBS News New York on Monday said they are hopeful the governor and mayor-elect can find common ground on free buses.

"That would be such a big help, you know? It's kind of tough out here," Kenyetta Wallace said.

"I think it's going to be great for people," Duhirwe Rushemeza added.