Nebraska's Congressional Delegation is urging president Barack Obama to approve the Keystone X.L. Pipeline.
Governor Dave Heineman just signed off on the project, saying there's little environmental risk.
The pipeline's opponents are still fighting to convince Obama to stop the project from happening.
Senators Mike Johanns and Deb Fischer joined Nebraska's three House members in signing the letter in support of the pipeline.
The letter says they believe the route and state's environmental review meet the Presidents criteria.
More than 50 senators signed a letter last week urging the President to approve.