With Hurricane Sandy preparing to sweep across the eastern United States today, officials said the Federal Emergency Management Agency has the funds in place to respond to the damage. But the severity of the storm raises the chances the agency will need to replenish its reserves in the coming months.

“FEMA is OK for now,” said one senior House Democratic aide. “If there is multibillion-dollar damage, though, that would be something to consider in November or December, when the damages are known. Obviously that will start a debate about how to ‘pay’ for a supplemental, which is typically viewed as emergency and over-and-above the budget.”

Sen. Charles Schumer (D-N.Y.) said at a news conference today that he expects federal help to begin quickly and without constraints.

“Due to the magnitude of the storm, I’m certain we’ll get a major disaster declaration, and we’ll get it quickly — as soon as the state officially applies,” he said. “Today, I’m calling on FEMA to skip the preliminary assessment and provide an expedited disaster declaration. They’ve done that on occasion. There is no question we will meet the limits, the $26 million limit we will meet, and so to wait a week and calculate everything while everyone is waiting and hoping and this-ing and that-ing doesn’t make much sense.”

Any need for new FEMA funding is likely to revive the debate over federal disaster relief that began in 2011, when House Republicans sought to require that emergency funding be offset by cuts elsewhere in the federal budget.

Democrats have highlighted that debate as new natural disasters have hit, and Schumer said similar debates may arise again if a supplemental appropriations bill is needed.

“There was a period of time a year ago where some folks didn’t want to fund disaster assistance, but we’ve overcome that and the disaster assistance funds are full,” he said.

With the coastline from North Carolina to New England facing a heavy storm surge expected to leave billions of dollars in damage, FEMA is benefiting from a September decision to spare the agency’s Disaster Relief Fund from the budget constraints faced by most federal agencies.

Congress left most of the government running at essentially flat funding to the previous budget year when it last month cleared a six-month continuing resolution. As is common under CRs, federal agencies were ordered to limit their activities as much as possible, but Congress left an exception for FEMA to spend the roughly $6.4 billion disaster allotment as needed.

“This funding will prevent any lapse in critical assistance to those already working to recover from these catastrophes, as well as adequate financial resources, should any need arise in the future,” House Appropriations Chairman Hal Rogers (R-Ky.) said last month while bringing the CR to the floor.

Aides for both parties today said it was too early to tell whether a supplemental appropriations bill would be needed. Lawmakers are expected to consult with key federal officials, including FEMA Administrator Craig Fugate, to get an assessment of the damage and any need for additional funds for disaster relief.

It helps that the hurricane is coming within the first month of the budget year and that there was a sharp drop in federal major disaster declarations in the previous year, with 34 called for 2011 following the record 99 In 2010. That means some fiscal 2012 funds likely are still available.

Still, Claire Rubin, a disaster relief consultant based in Virginia who has written a book on FEMA and state emergency response programs, said the agency eventually will need its own relief.

“They will run out of money,” Rubin said. “At a minimum, they are talking about damage in the low, single-digit billions. “If there is damage to a lot of public infrastructure, that will have to be paid for largely by the federal government.”