Should i ask him out?

ok so i have liked this guy for a while. i started to really like him in the past couple weeks. but then i found out that one of my best friends likes him too. sadies hawkins dance is coming up (where the girls ask the guys) and i really want to ask him. i think he likes me but i also think he may like her. i dont know what to do! BUT I LIKE HIM A LOT A LOT A LOT!!!!! please help me!