DENVER — Colorado Sen. Mark Udall is likely to vote against a possible amendment in the Senate this week that seeks to force the construction of the controversial KeystoneXL pipeline to transport oil from Canada to the Gulf of Mexico.

“Sen. Udall has been eminently clear that Congress should not inject politics into the administration’s ongoing review process,” said Mike Saccone, Udall’s spokesman. “That’s why he voted against Democratic and Republican amendments that attempted to dictate a result on the construction of the Keystone XL Pipeline.

“Any votes this week on the pipeline wouldn’t be any different.”

Senate Majority Leader Harry Reid is open to allowing a vote on the pipeline, which Republicans are clammoring for, as a way to give some of his most vulnerable incumbents an opportunity to demonstrate their support for KeystoneXL without actually approving the amendment itself.

Udall, a Democrat facing a tough reelection fight this fall against upstart GOP Congressman Cory Gardner, is under pressure to support construction of the pipeline and has said he’s open to doing so.

Millions of dollars are being spent lobbying lawmakers on this week’s possible vote; in fact, the oil and gas industry is running television ads in Denver urging viewers to encourage Udall and Sen. Michael Bennet, a Democrat, to support the Keystone pipeline.

Bennet hasn’t indicated how he might vote on a possible Keystone amendment this week.