A lot of good suggestion and I appreciate all the input. I'm gonna try to answer as many as possible with one post. Drummer and singer married so can't replace the singer. It's the singer and guitar plays band. I'm the newest one also the youngest. Mostly playing in biker bar to an older crowd 50+. We are playing at a new venue which is 21 - 30. I'm 29, I use to work at this venue for a year. I told her our songs will not work there. She is oblivious. I think I'm just gonna let them not ask us back and then fix it then.
You might be in a rough spot. It might be hard to gain traction with the drummer since he might be obligated to take her side. (Maybe not. But maybe.) The other person in the band, the guitarist, formed the band and thus is probably on board with the music selection. The other band members are older than you are, and it seems that they have historically played to an older crowd (and still do so in the biker bar). It sounds as though you're going to have an uphill battle here - but it really depends on how the rest of the band feels about it, and since you're the new guy, my guess is that they aren't going to want to budge much. That said, perhaps I'm wrong. If their desire to play new venues and make more money is greater than their desire to play the setlist they know, maybe you'll be in luck.
.....Hope you can come to some conclusion thru a group meeting or a diplomatic vote