The Senate starts at 2 p.m. on Monday and will later vote on whether to advance a bipartisan energy efficiency bill without any amendments.
Senate Majority Leader Harry Reid (D-Nev.) has offered to hold a vote the GOP has been demanding for more than a year, but Republicans want more.
Reid said he personally opposes the construction of the pipeline that would carry oil from Canadian tar sands to Gulf Coast refineries in Texas. The administration has delayed authorizing the pipeline for nearly five years, citing environmental concerns. But vulnerable Democrats up for reelection have supported a bill that would give congressional authority to grant the project.
After voting on the confirmation of two of President Obama's nominees Monday evening, the Senate will vote on whether to end debate on S. 2262. Sixty votes are needed to advance the legislation to a final passage vote.
Democrats will need at least five Republicans to join them in overcoming McConnell's filibuster on Monday. The underlying energy efficiency legislation has seven GOP co-sponsors, but McConnell has pressured them not to relent on forcing amendment votes.
Assuming McConnell doesn't cave and Republicans stand behind their leader, the Shaheen-Portman bill will once again fall short despite broad support. Their bill includes measures to boost building codes, train workers in energy-efficient building technologies, help manufacturers become more efficient and bolster conservation efforts at federal agencies, among other provisions.
At 5:30 p.m., the Senate will vote on the confirmation of Robin Rosenbaum to be a U.S. judge for the Eleventh Circuit and Steven Croley to be general counsel of the Department of Energy.
The House is not in session this week.