According to a February 2010 poll by the Pew Research Center, 61 percent of Americans said they favor allowing gays to serve openly, while 27 percent said they are opposed.
The House has already passed similar legislation. More recently, a federal judge in Los Angeles sided with a gay rights group and ruled that the military's policy violates due-process and free-speech rights.
Pop star Lady Gaga led a political rally in favor of repeal in Maine on Monday to pressure Collins and Sen. Olympia Snowe to side with Democrats on the issue. Lady Gaga said it was unjust to have goodhearted gay soldiers booted from military service while straight soldiers who harbor hatred toward gays are allowed to fight for their country.
She suggested a new policy should target straight soldiers who are "uncomfortable" with gay soldiers in their midst.
"Our new law is called 'If you don't like it, go home!'" she said.
Snowe has said she thinks the Senate should wait to act until the Pentagon completes its study.