Bloomberg met with more than a half-dozen lawmakers, including several who chair or sit on committees controlling the government's purse strings, as well and both parties' leaders in the House and Senate.
"Hurricane recovery is not a partisan issue," he told reporters at a news conference in between the meetings. "We have to bring together both sides in Washington."
New York state alone is seeking $42 billion in additional federal aid. New Jersey is seeking federal aid to cover most of the nearly $37 billion cost for recovery and rebuilding.
So far about $2 billion in federal funds - about half for direct assistance to individuals - have been provided to the two most heavily damaged states and nine others in the storm's path. There's about $5 billion left in the Federal Emergency Management Agency's disaster relief fund, but last year's budget agreement permits President Barack Obama to seek another $5.4 billion without hitting a ceiling on spending.
Sen. Susan Collins of Maine, a member of the Appropriations Committee and the top Republican on the Homeland Security Committee that oversees disaster relief, struck a skeptical note after her meeting with the mayor.
"It's going to be a hard sell," she said, given Congress's preoccupation with the fiscal cliff crisis and tight budget restraints. Reflecting a line taken in the past by House Budget Committee Chairman Paul Ryan and other fiscal conservatives, she said at least some of the new spending for Sandy relief and rebuilding should be offset by spending cuts in other government programs.
"Otherwise it's just going to be added to the debt and that makes it even more difficult for us to deal with the fiscal challenges," she said.
Collins said she needs to see more detailed numbers on damages before deciding on how much Sandy aid is needed. But she said New York's request is "reasonable" if the damages can be documented and added that state and city officials have not tried to exaggerate the damages, as she claims happened with Hurricane Katrina seven years ago.
Bloomberg and Schumer said they were pressing White House officials for as much money as possible, as soon as possible, but they didn't know what amount Obama will seek. Whatever it is, the request could get tied up in the talks aimed at averting the fiscal cliff - a $6 trillion combination of automatic tax increases and spending cuts - beginning in January.
"There's no doubt this is going to be a hard fight," said Schumer. "We have a Congress that is decidedly less friendly to disaster aid than any in 100 years. We're in very strenuous negotiations over the fiscal cliff. We know money is short in Washington, just as it is in New York."
Schumer said he expects the fight for Sandy money to drag on for months and that several emergency spending bills will be needed. State officials worry that Congress's desire to satisfy the hunger for aid will fade as time wears on.
"So far we believe our colleagues have been very receptive," said Schumer. "But there's a long road to go and there are going to be many pitfalls in the way, particularly given the climate in Washington and the shortage in money."
New Jersey Gov. Chris Christie said Wednesday that it's up to New Jersey's congressional delegation - made up of an equal number of Republicans and Democrats - to fight for the $37 billion in additional aid that he's seeking. He said he and New York Gov. Andrew Cuomo have agreed not to compete with one another for federal funds.
"We're not going to allow any political forces in Washington, D.C., to divide and conquer us," Christie said. "We going to go down there as a team, we're going to work together and advocate for the numbers we put forward."
States other than New York and New Jersey now getting federal aid for Sandy are West Virginia, Virginia, Maryland, New Hampshire, Delaware, Rhode Island, Connecticut, Pennsylvania and Massachusetts, as well as the District of Columbia.
Meanwhile, President Barack Obama has signed legislation allowing a pipeline through New York's Gateway National Recreation Area.
The president Tuesday signed a measure authorizing Interior Secretary Ken Salazar to issue permits to build and maintain the natural gas pipeline, which is aimed at boosting the region's access to natural gas.
The three-mile line would run from the Atlantic Ocean beneath Jacob Riis Park in the Rockaways and under Jamaica Bay to Brooklyn's Floyd Bennett Field. Some area residents and environmental activists have voiced safety and planning concerns about the project.
In a statement, Republican New York Rep. Michael Grimm says the project could create as much as $265 million in construction activity and 300 construction jobs. He calls it an important economic boost after Hurricane Sandy hit the region.
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