WASHINGTON — Standing before a 91-foot twin-trailer truck parked at the foot of the U.S. Capitol, three senior lawmakers from both parties said Wednesday they will fight to block Congress from endangering motorists by permitting 10-foot-longer semis on the highways, even though 38 states bar them.

Sen. Roger Wicker, R-Miss., led a news conference calling on his congressional colleagues to stymie the measure, which he said has zoomed to passage in the House of Representatives and is headed for the Senate floor without a hearing or a comprehensive safety examination.

“Why should Washington, D.C., be telling these states that we know better about safety decisions at the local level?” Wicker asked.

Among states that currently ban the longer tandem trucks are New York, California, Georgia, Kansas, Kentucky, Mississippi, Missouri, North Carolina, Pennsylvania, South Carolina, Texas and Washington. States that allow them include mainly wide-open Western states such as Alaska, Arizona, Idaho, Oregon, Montana, Nevada and Wyoming, but Florida does as well.

Wicker was joined by a diverse group opposing the bill, including Democratic Sens. Dianne Feinstein of California and Richard Blumenthal of Connecticut; Teamsters President James Hoffa, representing truck drivers; safety advocates; and a sizable slice of smaller trucking firms.

The truck expansion measure offered by Sen. Richard Shelby, R-Ala., passed the Senate Appropriations Committee by a single vote.

Feinstein noted that the twin-trailer assembly exceeds the height of an eight-story building.