A House subcommittee's vote to authorize construction of the $4.6 billion supercollider marks an important first step toward starting the massive physics project, and already several lawmakers promise the rest of the way won't be smooth.

The House subcommittee on energy and research development voted Thursday to spend $250 million on the Texas-based project in next year's budget.But panel chairwoman Marilyn Lloyd, D-Tenn., said the full Committee on Science, Space and Technology must still approve the project.

Lloyd's subcommittee approved the Energy Department's energy research and development budget with no debate on the collider, agreeing with President Bush's request for $160 million for initial construction of the project and $90 million for research and development.

Financing the supercollider at the $250 million level, however, means deep cuts will have to be made in other energy research projects, said Rep. Harris W. Fawell, R-Ill., and the shape of those reductions will influence his support of the superconducting supercollider.

Rep. Howard Wolpe, D-Mich., issued a statement saying he and Rep. Paul B. Henry, R-Mich., had reservations about the site selection process and the magnitude of the project.

In their joint statement, the Michigan congressmen said they believe "that the magnitude of contemplated national expenditure, combined with unresolved questions of procedure and substance on the site selection process, demands further review before recommending authorization for continued work on the project."

The men said they were concerned cost estimates on building the collider have "escalated dramatically since our last consideration of the issue."

Scientists hope the 53-mile underground tunnel will help them understand more about the fundamental nature of matter.