M.O.
You don't mention what her nap schedule is...
Perhaps she's sleeping too much during the day or too late in the day?
If she is napping, try to either eliminate her nap or give her a brief cat nap and then bump bedtime up. Make sure she's getting plenty of exercise late in the afternoon - sometimes hard with a little baby around I know...then give her a big dinner and a calm bath with lowered lights, voices, etc. then right off to bed for stories.
I hope this helps you! Been there too!