Democrats in Congress, allied with the trucking industry, are attempting to halt state efforts to lease toll roads to Macquarie Bank, Goldman Sachs Group, and other private investors.

House Democrats are considering withholding highway funds from states whose leases with companies fail to meet proposed federal standards. Critics of leasing say private investors are more likely to raise tolls than government authorities are. Private investors would also find it easier to fire toll collectors and other employees.

New federal restrictions could make investments in the $1.7 trillion of public roadways less attractive to private interests. And the mere fact of congressional attention might have a chilling effect on such deals, an analyst who works on toll-road transactions in the New York office of Fitch Ratings Ltd., which rates debt used to finance infrastructure, Mike McDermott, said.

For states with heavily traveled roadways, lease agreements with Macquarie or Goldman could be potential windfalls that would allow them to meet budget needs without raising taxes.

[A spokesman for the New York State transportation department told the New York Sun yesterday that leasing New York’s highways to private firms would require state legislation that has not been introduced, but that the department was open to creative funding options.]

Pennsylvania could raise between $12 billion and $18 billion by leasing the 537-mile Pennsylvania Turnpike, according to an analysis by Morgan Stanley. Governor Corzine is also looking at leasing state toll roads to raise money for highway construction and maintenance.

Goldman Sachs, the biggest American securities firm by market value, raised $6.5 billion last year for a new fund to invest in toll roads and other infrastructure. Goldman Sachs is one of 48 firms that have expressed interest in leasing the Pennsylvania Turnpike.