Senate Republicans steered legislation to approve the Keystone XL oil pipeline toward an initial test vote on Monday, intent on forcing a quick veto showdown with President Barack Obama over the long-stalled project.

The measure has sparked intense debate over the Canada-to-Texas pipeline's potential impact on employment and the environment, yet there was little or no doubt that it would overcome Monday's hurdle. Republicans said they hoped it could win final approval and be sent to the White House by the end of next week.

"President Obama has every reason to sign the jobs and infrastructure bill that we will pass," said Senate Majority Leader Mitch McConnell, of Kentucky. He noted that the Nebraska Supreme Court had recently rejected a legal challenge brought by opponents, an obstacle the White House had cited.

Sen. Brian Schatz, D-Hawaii, made the case for the opposition. He said that if constructed, the pipeline would carry "some of the dirtiest, most dangerous and most polluting oil in the world." He called the project "anti-clear water, anti-clear air, anti-public health."

The proposed 1,179-mile pipeline would begin in Canada, enter the United States at Morgan, Montana, cut across South Dakota and connect with an existing pipeline in Steele City, Neb., that, in turn, reaches refineries along the Texas Gulf Coast. It would carry an estimated 800,000 barrels of crude oil a day.

The White House has repeatedly threatened a veto, and if Obama follows through, it will become the first of what are expected to be numerous clashes with the Republican majorities now in control of both houses of Congress.