Sen. Harry Reid, D-Nev., said the criticism was misguided, and that backing for the magnetic levitation, or "maglev," train venture should be anything but controversial. The spending was authorized by Congress three years ago but a drafting error froze the authority for money to be released, he said.

Sen. Barbara Boxer, D-Calif., chairwoman of the Environment and Public Works Committee, said the maglev provision "is just a technical correction. It does not change one thing."

But Sen. Jim DeMint, R-S.C., said it makes several subtle changes with the effect of dedicating money to the project. The venture envisions whisking travelers at speeds up to 300 mph along Interstate 15 between Las Vegas and Primm, and then eventually to Anaheim, Calif.

In so doing, DeMint said the bill would threaten a rival project, Desert XPress, whose investors say they are working to establish high speed diesel-electric train service along Interstate 15 without taxpayer help.

The maglev train funding issue has emerged in what normally would be a routine technical bill. The intent is to set straight drafting errors made in a major highway bill Congress passed in 2005.

Democrats have promoted the technical corrections bill as an economic stimulus that would free up as much as a $1 billion for infrastructure projects that create jobs.

Sen. John Ensign, R-Nev., has not said whether he supports or opposes the bill.

The furor over maglev funding also is providing a glimpse of a behind-the-scenes rivalry surrounding train service plans to and from Southern Nevada, several officials said Tuesday.

American Magline Group is promoting the maglev project between Las Vegas and Anaheim, Calif., in partnership with Nevada and California authorities, while Desert XPress envisions conventional high-speed trains traveling at speeds up to 125 mph along the Interstate 15 corridor between Las Vegas and Victorville, an hour and a half northeast of Los Angeles.

"It's been pretty well known," said M. Neil Cummings, president of American Magline Group, a consortium of vendors and investors backing the maglev project. Desert XPress "has been exerting influence because they do not want to see our project succeed."

Among the backers of Desert XPress is Las Vegas power broker Sig Rogich, who sources said has been making a case to senators in favor of that project.

Rogich was traveling in South Korea on Tuesday, his office said, and was not available.

In February, he told Associated Press, "I'm hoping that the Senate as a whole will look at what's been spent to date and ask specifically what is this $45 million for."

Tom Stone, president of Desert XPress, said his team does not consider the maglev project to be a competitor. Simply, the federal government does not have the money that will be needed to complete the line, he said.

"If we could see a way for maglev to be funded, we probably would be trying to make that happen," Stone said. "But we couldn't see a way." Desert XPress says it will not require federal funds.

The release of $45 million in federal funds for maglev, most of which would be directed to the Las Vegas-Primm segment of the route, "doesn't affect our project," Stone said.

Contact Stephens Washington Bureau Chief Steve Tetreault at stetreault@reviewjournal.com or 202-783-1760.