Whether Harry Reid will actually put their legislation to a vote or not is still up in the air, but Republican John Hoeven and hyper-vulnerable red-state Democrat Mary Landrieu made a hard push this week to rally support for their jointly proposed measure to immediately greenlight the Keystone XL pipeline. All of the Senate’s Republicans as well as eleven Democrats are already officially on board, which means they’re only a handful of “yeas” away from the 60 votes they would need to clear any procedural hurdles (although getting the 66 votes they would need to overcome the presidential veto threat the White House will likely issue is probably another matter entirely).

Conspicuously absent from that list of at least eleven Democrats so far, however, are the two senators from Colorado, via the WSJ:

Senators from both parties who are pushing the bill are eyeing the Democrats from Colorado as potential yes votes on the bill.

Mr. Bennet voted yes on a nonbinding measure last year supporting the project, and Mr. Udall has voted against it in the past.

Mr. Udall, first elected to the Senate in 2008, is running for re-election against GOP Rep. Cory Gardner of Colorado. Representing a major oil-and-gas producing state, Mr. Udall has faced increasing pressure to take clearer positions on energy issues like Keystone ever since Mr. Gardner entered the race a couple of months ago.

“I think there is a reasonable argument that the pipeline is in the national interest. I also think there are serious questions about air quality, water quality and land-use effects on the pipeline,” Mr. Udall said in an interview in Denver on Saturday. “Am I frustrated it’s taken this long? Yes, but the important goal is to get it right.”

Sen. Bennet has reaffirmed his general support for the pipeline pretty recently, although he has yet to add his name to Landrieu’s coveted legislation — but he’s not the one up for imminent reelection here. Colorado is the country’s fourth-largest natural gas producer and sits atop some major oil fields, and relatively speaking, energy issues are enormously important; since Sen. Udall and Rep. Cory Gardner are birds of a feather when it comes to certain other aspects of the energy debate…

Sen. Mark Udall (D-Colo.) said late Thursday that he is replacing his proposal to expedite liquefied natural gas (LNG) exports with a bill sponsored by Rep. Cory Gardner (R-Colo.), who is challenging Udall for his seat.

“Colorado’s natural gas resources have a central role to play in creating jobs and promoting global stability,” Udall said in a statement. “This effort to expedite natural gas exports to our allies and trading partners abroad is far too important to get bogged down over technical differences between the two chambers.”

The House Energy and Commerce Committee passed Gardner’s bill Wednesday. When he first proposed the measure, it sought to force the Department of Energy (DOE) to quickly approve all LNG export applications for countries in the World Trade Organization (WTO). But the bill that passed the committee was watered down and instead set a timeline for DOE to consider applications.

Udall’s bill similarly would have opened LNG exports to WTO countries.

…and seeing as how their race is locked in a dead heat, I doubt Gardner is going to allow Udall to get away with anything less than a hard stance on the pipeline for long without making it a huge headache for him. Outside groups certainly aren’t — especially since Udall, for his part, has recently been spotted mingling with avidly anti-Keystone eco-radical progressive billionaire Tom Steyer at one of his mega-money San Francisco fundraisers. Awkward.