Lady Gaga will visit Maine's largest city to join a rally against the US military's ban on service members being openly gay.The singer is expected to join a Servicemembers Legal Defense network event near the University of Southern Maine's Portland campus. A network spokesman said she will stand alongside veterans discharged because of the military's so called don't ask,don't tell policy. The policy forbids recruiters from asking about people's sexual orientation and prohibits service members from revealing if they are gay. The network is trying to pressure Republican senators from the state to vote to allow a repeal of the policy. Lady Gaga recently called on Senate majority leader Harry Reid to repeal the policy during an interview with TV host Ellen DeGeneres.