With her chamber stuck at 59 votes in favor of Keystone XL, Senator Mary Landrieu, a Louisiana Democrat, worked hard to gather one last vote needed to pass a bill that the House of Representatives approved on Friday. The Senate is expected to vote as early as 6:15 p.m. EST on Tuesday on TransCanada Corp's project that would transport more than 800,000 barrels per day of oil.
Republicans including Senator John Hoeven, from North Dakota, also pressured Democrats. All 45 Republicans support the pipeline, so they need 15 Democrats. Several Democrats thought to be persuadable said last week they will vote "no."
Obama criticized the project during a trip to Asia late last week, saying it would not lower fuel prices for drivers, but would allow Canada to “pump their oil, send it through our land, down to the Gulf, where it will be sold everywhere else."
On a call with reporters on Monday, Obama adviser John Podesta reiterated Obama's message: "I would just repeat what he said, which is we ought to take the time to let the process play out and let the analysis come in."
Republicans and energy analysts said those comments likely meant Obama was leaning toward vetoing any Senate Keystone bill that passes, either this year or early next year.
"The President ... is basically threatening a veto this time," said Ryan Bernstein, an aide to Hoeven, who is sponsoring the bill with Landrieu. "Obviously, this makes it harder to gather votes because he is sending a signal to Democrats on which way he thinks they should vote."
Many environmentalists oppose Keystone, saying it would spike emissions linked to climate change and that the oil could be sold abroad. Construction workers and other supporters say it would create thousands of jobs.
Hoeven plans to reintroduce the bill in January or February if it does not pass on Tuesday. Supporters could introduce a standalone bill or attach Keystone language to another bill that would be hard for Obama to veto.
Republicans say they will have 60 votes next year after the party's strong showing in this month's U.S. midterm elections which will give them new senators including Joni Ernst of Iowa, Cory Gardner of Colorado and Shelley Moore Capito of West Virginia.