Louisiana Democrat Sen. Mary LandrieuMary LandrieuFive unanswered questions after Trump's upset victory Pavlich: O’Keefe a true journalist Trump’s implosion could cost GOP in Louisiana Senate race MORE's biggest election opponent is urging her to act on legislation that would stop the delay of the Keystone XL pipeline.
Rep. Bill Cassidy and the rest of Louisiana's House Republican delegation urged Landrieu on Monday to use her power as head of the Senate Energy Committee to push for a vote on a House-passed bill that would remove the need for a presidential permit for Keystone.
But before Cassidy sent the letter pressing Landrieu to take action, she tweeted that she intends to press for a vote to green-light the project in the coming weeks.
Still, Cassidy said he "hope the Senate also overcomes the resistance of President Obama and Senator [Harry] Reid [D-Nev.] to build the Keystone pipeline."
"I voted with the House of Representatives to bypass President Obama and get the pipeline built," he added.
Cassidy's move to put pressure on Landrieu might help him come November if Landrieu isn't able to follow through with threats to propose legislation on Keystone, a project both lawmakers support.
Cassidy announced his run against Landrieu in early April, making her reelection bid as an already vulnerable Democrat even more difficult.