WASHINGTON — During a grand presentation in the ornate rotunda of New York Penn Station last month, U.S. Transportation Secretary Ray LaHood was Santa Claus in a gray suit, handing out more than $2 billion for rail projects.

Nearly half a billion dollars was to go toward electrical upgrades on the Northeast Corridor between Trenton and New York City, bringing relief to beleaguered commuters on America’s busiest rail line.

Now that funding is threatened by a most unlikely source — a New Jersey congressman who thinks the money would be better spent hundreds of miles away, for flood relief in the Midwest.

U.S. Rep. Rodney Frelinghuysen (R-11th Dist.) proposed an amendment that would divert $1 billion of the money for relief in areas ravaged by flooding along the Mississippi and Missouri rivers. The amendment was passed last week by the House Appropriations Committee, but still needs full House and Senate approval.

"It’s very discouraging that a congressman from New Jersey, although he has good motivations, should really rob Peter to pay Paul in this action," said New Jersey transportation expert Martin E. Robins, director emeritus of the Alan M. Voorhees Transportation Center at Rutgers University.

The money would presumably go to help problems such as the one that made Tuesday's commute a nightmare for thousands of passengers: A transformer fire early Tuesday in New Brunswick caused the loss of power on most of the Northeast Corridor in New Jersey.

Robins said if rail money is taken away, it "pushes even further back into the queue" efforts to replace the decrepit Portal rail bridge over the Hackensack River or build the Gateway rail tunnel from Secaucus to New York Penn Station.

A spokesman for Frelinghuysen said the rail money — initially turned down by Florida — was still up for grabs.

"The bottom line is, Congress has not seen any U.S. Department of Transportation plans for this money," Steve Wilson said. "There have been no grant agreements. There are no grant monies that have been sent out with respect to this funding. This funding without a doubt remains unobligated today, and therefore, eligible to be rescinded."

However, a senior DOT official said the Federal Railroad Administration has been working to get grant agreements in place for the remaining unobligated funds. And all along the intent had been that it would be transportation money, the official said.

The Northeast Corridor from New Brunswick to a little south of Trenton was to get $450 million for improvements — including replacing the Depression Era overhead train "catenary" wires and upgrading the electrical system — that would allow speeds up to 160 mph and increase overall reliability. Amtrak Acela trains now travel about 135 mph in that stretch of New Jersey.

Sagging or frayed wires from weather conditions or aging are a common source of delays on the Northeast Corridor. The improvements would have taken about six years to complete, officials said.

Ya-Ting Liu, federal advocate for the Tri-State Transportation Campaign transportation advocacy group, said the effort to rescind high-speed rail money intended for New Jersey and other states is not likely to pass the House or Senate, particularly with U.S. Sen. Frank Lautenberg (D-N.J.), a huge proponent of transportation in New Jersey, standing in the way in the Senate.

Asked to comment on the potential for New Jersey rail money to be spent elsewhere, Lautenberg spokesman Caley Gray said, "Sen. Lautenberg is a member of the Senate Appropriations Committee and will fight to make sure federal funding designated for New Jersey stays in New Jersey."

Gov. Christie’s office had no comment.

Liu said that despite the unlikeliness of New Jersey’s rail money being spent elsewhere, the battle among political leaders over high-speed rail has implications that could affect the future of transportation in the state.

"It’s pretty much the lifeblood of our economy," Liu said.

"The floods are a huge issue and I can appreciate the idea of taking the macro view when it comes to allocating resources," said Josh Crandall, founder of the Clevercommute.com commuter website. "But the commuting public will continue to lose out if strategic funds are continually at risk of being diverted for emergencies or acts of nature. From an infrastructure point of view, we’ll never get anything done if we behave this way."