Sen. Trent Lott proposed new restraints on home-district spending projects known as earmarks Thursday, but vowed to "fight like a tiger" against eliminating a practice that has spurred calls for higher ethics in Congress.

Lott, chairman of the Senate Rules Committee, and Sen. Dianne Feinstein, D-Calif., jointly proposed a change that would give senators the opportunity to kill special projects inserted, often without the knowledge or vote of other senators, in larger pieces of legislation.

The Lott-Feinstein measure is the latest of a number of clean-government proposals to come out of Congress as lawmakers react to scandals involving bribery and unethical or illegal lobbying practices.

Earmarks, said Feinstein, are often "put in in the dark of night by people who have substantial power and authority." There's no question, Lott said at a news conference, "that the practice has exploded over the years."

There were an estimated 14,000 earmarks or pork barrel projects inserted into legislation in 2004, more than triple the number of a decade earlier, according to one congressional study. The value of these projects, ranging from highways to defense contracts, was put at $52 billion, nearly double a decade earlier.

The Lott proposal, to be discussed at a hearing of his committee next week, would require House-Senate compromise bills to be made available at least 24 hours before they are taken up by the Senate so that members can see what's in them. These reports must include a list of the sponsors and justification for all earmarks.

Many members have complained that House and Senate leaders, when negotiating bills, insert earmarks into the compromise version that neither body has voted on. The source of the earmark is often unknown.

The proposal also says that any member could raise a point of order on any earmark inserted in the House-Senate conference report, eliminating it from the bill unless the point of order is overridden by a 60-vote majority.

Several House members have also addressed the earmark issue in ethical reform legislation.

One proposal, by Reps. Jeff Flake, R-Ariz., and Harold Ford, D-Tenn., would bar agencies from funding earmarks unless they are contained in the actual legislative language of a bill. Often, earmarks are written into the committee report that accompanies a bill, which can't be amended on the floor.

Lott, R-Miss., formerly the Senate Republican leader, noted that some lawmakers, including Sen. John McCain, R-Ariz., have long pushed for eliminating all earmarks from legislation. "It's not going to happen," he said, adding that there is nothing wrong with lawmakers trying to advance the interests of their constituents with legitimate projects.