Landrieu did not immediately respond to a request for comment on the demonstration.
The demonstrators argued the proposed 1,700-mile-long pipeline from Canada down through Texas could lead to oil spills along the route and could accelerate the impact of climate change.
“For somebody that had the gulf oil spill and the devastation that that brought to her state, as well as the entire Gulf [of Mexico] coastline and the gulf [waters], she should understand how important it is that we don’t have these types of environmental disasters,” said Art Tanderup, a Nebraska farmer and member of the Cowboy Indian Alliance, a group that opposes the pipeline. “Unfortunately, cleaning up the gulf was a piece of cake compared to what it's going to be to clean up a tar sands spill in the Ogallala aquifer.
"Keystone XL is going to be the turning point," Tanderup added. "We either go backwards in time with Keystone XL, or we move forward and say this country is going to do what it should have been doing for several years, and work ourselves away from these dirty tar sands, and get us into that clean energy environment."
The Senate is slated to hold a vote on authorization of the pipeline on Tuesday and currently appears just one vote short of crossing the 60-vote threshold.