Organizers say Lady Gaga is attending a rally in Maine's largest city against the military's "don't ask, don't tell" policy on gays, which is up for discussion in the Senate this week.
The singer is expected to join a Servicemembers Legal Defense Network event near the University of Southern Maine's Portland campus at 4 p.m. Monday.
Network spokesman Trevor Thomas says she'll stand alongside veterans discharged because of the policy, which forbids military recruiters from asking about people's sexual orientations and prohibits service members from revealing if they're gay.
The organization is trying to pressure Republican Sens. Olympia Snowe and Susan Collins of Maine to vote to allow a repeal of the policy. Collins previously voted for a provision to repeal.
Lady Gaga recently called on Senate Majority Leader Harry Reid to repeal the policy during an interview with TV talk show host Ellen DeGeneres.
The Senate is scheduled to consider the matter Tuesday.