WASHINGTON — President Obama is finding himself increasingly boxed in on the Keystone pipelinefight as more Congressional Democrats are joining Republicans in backing the project, which has strong labor support and could generate significant numbers of jobs in economically hard-hit states.
On Wednesday, the House passed a short-term transportation bill that included a provision that would pave the way for the construction of the next stage of the oil pipeline, a measure that Mr. Obama has said he would veto. The bill passed 293 to 127, with 69 Democrats supporting it.
It is the fourth time the House has passed a measure to expedite the project; one failed narrowly in the Senate only after Mr. Obama personally lobbied some Democrats to vote no. With the House vote, Mr. Obama finds himself, for the first time in his presidency, threatening a veto on a significant piece of legislation that enjoys the support of an increasing number of Democrats, as well as the vast majority of Republicans in Congress.
With gas prices sticking near $4 a gallon, unemployment high in many states and demonstrable support for the project in numerous polls, many Democrats — especially those from states where pipelines are commonplace — are beginning to sound almost indistinguishable from Speaker John A. Boehner, who called Mr. Obama “increasingly isolated” in his opposition to expanding the project.
Representative Dennis Cardoza, a California Democrat who voted for the House measure, said he would be happy to vote to override a veto if needed. He said: “I think the president has made a very serious mistake here. I’m still supporting the president. But we have to do what’s right.”
The pipeline expansion was deemed suitable last year after extensive review by the State Department, but it was prevented because of concerns in Nebraska — including those pressed by Gov. Dave Heineman, a Republican — over the proposed route. Mr. Heineman called a special session of the Legislature that resulted in a law requiring a modified route, but the Obama administration, facing continued protests from environmental groups that are resistant to new pipelines period, said it would delay a decision on the new route until after the election.
Republicans were enraged, arguing that the project could begin while a new Nebraska route was cobbled together, and passed various bills to circumvent the administration.
Wednesday’s vote came the day after Mr. Heineman signed a bill to review a new version of the project quickly.
In addition, TransCanada , the company behind the project, said this week that it had created a new routethrough Nebraska that would avoid the environmentally sensitive Sand Hills region and the Ogallala Aquifer. But the State Department, which has some measure of control over the project because it crosses international borders, would still need to review a new submitted plan.
All year, House Republicans have made it a central goal to win approval of the pipeline, which would stretch from oil sands formations in Alberta, Canada, to refineries on the Gulf Coast. The number of jobs that could be created by the Keystone expansion — supporters say 20,000 — is disputed. But many companies and unions around the country have been clamoring for the extension.
Now that the House has approved a transportation bill that differs from one passed in the Senate, the two chambers must go to conference. Because of the pressure on both parties to pass a highway measure, the thirst for compromise will be high.
"I think the president has made a very serious mistake here."
Central to the theater will be Senator James M. Inhofe, Republican of Oklahoma, and the Democrat who is co-author of the Senate highway bill, Barbara Boxer of California.
“At the end of the day,” said Matt Dempsey, a spokesman for Mr. Inhofe, “people really want the highway bill done. Keystone has gotten overwhelming bipartisan support in both chambers. So that puts President Obama in an awkward spot where these two things match up together.”
Ms. Boxer, who has called for a “truly bipartisan” bill, would not comment on the prospects for the conference committee. And Representative Steny H. Hoyer of Maryland, the minority whip who supports the project, would not be thrilled if House Democrats were to have to deal with a veto.
Senator Harry Reid of Nevada, the majority leader, was noncommittal on Thursday in a news conference. “It’s pretty clear now how we stand on this issue,” he said. “We’ve voted on it a number of times. But maybe somebody will come up with some magic formula that will allow us to do more.”
Jay Carney, the White House spokesman, did not dig in one way or the other on Thursday. “They seem to have taken a step in Nebraska to meet requirements set by the Nebraskan Legislature,” Mr. Carney said. “And as the president said when he was in Oklahoma, we anticipate a submission by TransCanada in the future, and we’ll judge it accordingly.”
But Democrats like Senator Bob Casey of Pennsylvania say they would support a highway bill with a Keystone pipeline provision. “I would vote for it, yes,” Mr. Casey said.
Democrats beyond Washington — including those who run unions, build pipeline parts and run cities or states — have also been big supporters of the project. “Cool down, cowgirl,” said Gov. Brian Schweitzer, Democrat of Montana, when told about the current situation in Congress. “I am a very large advocate of Keystone, and it disgusts me that instead of solving the issue, the people in Washington just fight.”