Boxer said there were "starkly different approaches" to the federal transportation bill in the House and the Senate. But, she quickly added, "I don't think it is necessary to bemoan that fact, but necessary to recognize it."
"Whether you like the president or you don't, this has nothing to do with that," she said.
Transportation advocates have latched onto Boxer's bill because it would spend more per year on road projects than Rep. John Mica's (R-Fla.) measure in the House. But even Boxer's bill is far less than $556 billion over six years, which was proposed earlier this year by President Obama.
Still, transportation supporters said Thursday in the Senate committee meeting the 35 percent that observers say would be cut from current transportation funding under the House bill would be too much for most states to bear.
"Madam Chair, simply put, we need to at least maintain current funding levels in order to sustain over 500,000 jobs while we leave behind transportation assets that will be critical to the long-term economic competitiveness of our country," Nevada Transportation Secretary Susan Martinovich told the Senate committee Thursday.
Mica has argued that the transportation bill can spend more than is brought in by the Highway Trust Fund that funds it, which limited him to about $35 billion per year. If the bill being on the floor at the Senate hearing Thursday was enacted, the highway trust fund would be insolvent by 2013, Mica says.
But Martinovich said cutting back transportation funding to $35 billion "would have a devastating effect on many state transportation programs."
"While the states would prefer the more typical six-year reauthorization bill, two years of stability at current funding levels is a vast improvement over what we have had with six extensions over the past two years," she said. "This provides the opportunity to make a down payment on the long-term bill the States need."
Republicans on the Senate Public Works panel appeared to be more sympathetic to that argument than their counterparts in the House have been, though they too acknowledged it would be difficult to allocate more money to transportation than the highway trust fund brings in.
"A two-year bill provides opportunity to advance to that goal, and it's a vast improvement over uncertainty," Sen. Jeff Sessions (R-Ala.) said Thursday. "We'll do dead level best to maintain this level of funding this committee proposes. Whether or not we can do that, I don't know."
Sessions said that states need to change their approach to transportation projects, even as member of Congress are gearing up to dole out more money.
"I think some of our governors and politicians, they promised 20 roads, but they've got money to complete 10," he said.
Democratic Sen. Tom Carper (Del.) said the Senate and the House needed to "to set aside our differences and move ahead, and try to do more good than bad."
"If we don't have a modern infrastructure, we'll be a second-class nation sometime," Carper said. "It's just critical."
Carper made the case for finding new revenue to pay for transportation projects by raising the federal gas tax, an issue that is a political nonstarter for the tax-averse GOP-led House. Even Obama has disavowed the proposal, saying it would burden people already struggling in downtrodden economy.
But "at the end of the day, we need to raise some revenues," Carper said Thursday. "It'd be smart if we could raise some revenues in away that reduced our dependence on foreign oil."
Boxer did not comment on the gas-tax proposal, but she lauded Republicans on her committee for supporting her bill.
"We have reached a milestone today in the bipartisan support for this bill," she said. "I think this is a day that we'll remember for a long time."
It remains to be seen, however, if there can ever be agreement with the House.
The current short-term transportation bill expires in September.
This post was corrected July 22 at 10:15 a.m.