WASHINGTON - Dont look for a long-term federal highway and public transportation bill to hit the floor of the U.S. Senate before spring, with passage problematic after that, says the chairwoman of the Senate Environment and Public Works Committee.

Sen. Barbara Boxer, D-Calif., said last month she was preparing to finish committee work on the new highway bill by spring. Meanwhile she is seeking a six-month extension of the existing law.

"Getting a bill out is what Id like to do," Boxer told reporters at the conclusion of a meeting with U.S. Department of Transportation officials.

She cautioned, however, that while her committee could finish by spring, a timetable for passage by the full Senate was not her decision.

Currently she is "focused on the six-month extension" of the law that expired in September. Congress has twice passed short-term extensions for the law as part of bills to continue funding the government while completing other overdue long-term spending bills.

The latest extension expires Dec. 18.

Boxer, other Senate committee chairmen and ranking Republicans wrote to Senate Majority Leader Harry Reid, D-Nev., and Minority Leader Mitch McConnell, R-Ky., asking them to bring a six-month extension to the floor for a vote this month.

Previous attempts to pass multi-month extensions have stalled on the Senate floor because of Republican objections.

Those extensions have cut the amount of money available to states by as much as 30 percent, according to USDOT officials. However, since many states have unused funds still to tap, and the winter months generally slow construction spending, the problem is not yet considered acute.

By extending the highway bill as part of continuing resolutions that fund the government, DOT said, it is forced to cut back on how much money it can allow states to spend. The Senates independent extension would reverse this rescission of funds.

Boxer said that while she continues to favor the longer, 18-month extension that would restore that lost funding and has been supported by the White House, "I cant convince the House."

In the House, several transportation leaders, most notably Rep. James Oberstar, D-Minn., have steadfastly opposed a long extension, instead preferring to work out a series of short-term stopgaps with the hope of passing new, long-term legislation.

Boxer said the Houses tactics have brought transportation funding to "a crisis point" so they could "double the gas tax."

She said she couldnt support that because "I dont have the votes in this committee to do that, let alone in the full Senate. Im reflecting reality."

Even if the Senate passed a six-month stopgap, theres no guarantee such an extension would win Oberstars support.