Thirty-seven Democratic senators have penned a letter sent to President Obama Thursday urging him to sign an executive order to pass the Employment Non-Discrimination Act (ENDA) prohibiting discrimination on the basis of sexual orientation or gender identity. Currently, employers are barred from discriminating on the grounds of race, color, religion, sex, or national origin–rights provided through an executive order signed by Lyndon B. Johnson in 1965. But the 37 senators, led by Oregon Democrat Jeff Merkley, are calling for an extension to the existing laws. “Issuing an executive order that includes sexual orientation and gender identity is a critical step that you can take today toward ending discrimination in the workplace,” the letter to Obama says. The bill has been introduced in Congress every year since 1994, except in the 109th Congress, but has yet to be passed. In 2011, former Massachusetts congressman Barney Frank introduced a transgender-inclusive version of the bill, which was then introduced in the Senate by Merkley.