Senate Republicans on Wednesday failed in an effort to undercut the National Labor Relations Board's authority to challenge a company decision on where to locate its work force.

The immediate challenge to the NLRB is focused on the board's complaint against Boeing Co., which opened a production plant for its 787 Dreamliner in right-to-work South Carolina.

Democrats, who defeated the move in the Senate Appropriations Committee, said the Republicans were trying to overturn 75 years of labor law designed to protect workers.

The proposal by Sen. Lindsey Graham, R-S.C. failed on a mostly partisan 15-15 vote. Sen. Mark Pryor, D-Ark., supported Graham. All other committee Democrats voted against the amendment to a larger spending bill, while all Republicans supported it.

The tally blunted a vote last week in the Republican-dominated House in favor of undercutting the board's authority. The Republican effort is unlikely to win approval in the Democratic Senate, but it gives the party a campaign issue for the 2012 elections.

The Appropriations panel also decided to give President Barack Obama just a small fraction of the money he wants to build high-speed rail lines, one of his leading economic priorities.

On a voice vote, the committee included $100 million for the rail program in a massive measure financing 2012 federal transportation and housing programs. Obama wants to spend $8 billion next year for the rail systems, in which trains can travel between cities at up to 250 miles per hour.

No. 2 Senate Democrat Richard Durbin of Illinois said, "We understand the budgetary constraints." Durbin sponsored the amendment adding the money.

High-speed rail now faces a dismal future in Congress, at least in the short term. A subcommittee in the Republican-run House has approved legislation denying any money for the project next year.

Sen. Patty Murray, D-Wash., author of the overall $110 billion transportation and housing bill, included nothing for high-speed rail in the original version of the legislation. She cited tight spending constraints that lawmakers face as they struggle to control ballooning federal deficits.

Durbin said the $100 million for the rail work would be paid for with unspent money from past home district projects called earmarks.

Obama has proposed a $53 billion, six-year high-speed rail initiative. He says the project would spur the languid economy, produce jobs and help make the U.S. more competitive with other countries that already have fast rail service.

The Appropriations panel approved the transportation-housing bill by 28-2.

The Republican move on the NLRB reflected the views of business groups, who argue the labor board has no right to tell a company where to locate its work force. The NLRB filed a complaint in April that alleges Boeing violated labor laws when it opened its South Carolina production line. The board's acting general counsel, Lafe Solomon, said Boeing went to the right-to-work state to punish union workers in Washington state for past strikes, and wants the work moved to the West Coast.

Graham argued that Boeing made "a business decision for business reasons," and said if the NLRB is successful, "the next decision will be to leave the country."

"This is a stop-the-madness amendment," Graham said. "Where they will go for sure next time, they will go to China," he said.

Sen. Patty Murray, D-Wash., countered that Graham was trying to interfere "in the middle of the game" in a legal case that is now before an administrative law judge. She said Graham's amendment would be similar to intervening in a civil or criminal court case.

"This is not a right-to-work issue," she said. "It's a retaliation issue."