Senators approved the bill, which will pay for road construction and mass transit programs over the next six years, by a vote of 76-21 after defeating an attempt by some Republicans to pare it back to Bush's $256 billion request.
"This bill that we passed is a good bill. We've heard all kinds of criticisms ... but nonetheless we will get a lot more miles literally for the dollar than we ever have before," said Republican Sen. James Inhofe of Oklahoma, chairman of the Environment and Public Works Committee, who shepherded the measure through the Senate.
The bill, which usually generates little controversy because of the jobs and economic stimulus it generates, has become an early referendum on Bush's election year goal of slashing the ballooning deficit.
"With passage of an excessive $318 billion highway funding bill, the Senate today missed an important opportunity to rein in spending," White House spokesman Scott McClellan said in a statement.
McClellan reiterated the administration's threat that Bush will veto any bill that is too expensive and included funding mechanisms the administration could not accept.
Senate Majority Leader Bill Frist said he was sure once the House finishes work on its own stalled $375 billion version, the final bill would be pruned during House-Senate negotiations.
"I am convinced that as this bill proceeds, we can find ways to reduce its cost and address the concerns posed and raised by the president," the Tennessee Republican said in closing the debate.
Some senators said the bill should have included a fuel tax increase, a funding mechanism that top lawmakers backing the House bill had also hoped to use but that Bush has rejected.
Bush also objects to the Senate's bill's use of certain fuel tax-related revenues that currently are deposited in the general fund but which some senators feel should be dedicated to highway projects.