Sen. Joe Lieberman (ID-Conn.) on Tuesday attracted nine new backers for his bill to overturn the military’s controversial “don’t ask, don’t tell” policy, but a Republican co-sponsor continues to elude him.

In a statement, Lieberman announced his bill drew the support of Democratic Sens. John Kerry (Mass.), Dick Durbin (Ill.), Charles Schumer (N.Y.), Frank Lautenberg (N.J.), Sherrod Brown (Ohio), Tom Udall (N.M.), Bob Casey (Pa.) and Russ Feingold (Wis.). Sen. Bernie Sanders (I-Vt.), who caucuses with the Democrats, also signed on as a co-sponsor to the legislation.

“I am honored that nine more of my colleagues have decided to co-sponsor this bill, which will end discrimination against American soldiers, sailors, airmen, and Marines on the basis of their sexual orientation,” Lieberman said in the release, adding that the bill would help “increase military readiness and maintain the high standards of conduct we expect of our service members.”

President Barack Obama tapped Lieberman to lead the legislative push to reverse the policy banning gays from serving openly in the military. While Democrats largely support the endeavor, moderates don’t want to take legislative action until the Pentagon completes a yearlong review on the effects of overturning it. Lieberman also wants to push a bipartisan bill but has so far been unable to secure GOP support.