ALBANY – With more than 1 million homes and businesses still without power in New York City and on Long Island, and recovery and cleanup costs mounting, the state’s chief fiscal watchdog said Friday the economic impact from Hurricane Sandy could top $18 billion for New York State.

State Comptroller Thomas DiNapoli said his office will have a preliminary projection completed next week for how the storm might also affect the state’s own finances.

The new projection by DiNapoli came as Gov. Andrew M. Cuomo said he struck a deal with the leaders of the Assembly and Senate to pledge $100 million in state money “dedicated to victims of Sandy.”

The money, which would either have to come from some other state funding pots or be appropriated in a special session of the Legislature, could go for such things as helping to fund home repairs, or at least those repairs presumably not covered by insurance or the federal government, the governor said.

In Manhattan Friday morning, Cuomo said if the $100 million is not enough, “Then we’ll reconsider that program, and I’m sure we would renew and replenish that program.”

The $100 million could be a costly endeavor in the months ahead for the state government, which already is facing a $1 billion projected deficit in the next fiscal year beginning April 1. And DiNapoli already has said state revenues are off by more than $400 million from what Cuomo and legislators estimated when they put together the current year’s budget back in March.