Elphaba or the broom?

I’ve seen the movie too many times to count and still can’t make up my mind.

Is the broom what gives Elphaba the power to fly or is it more of a Dumbo magic feather thing?

She clearly has the ability to fly short distances during The Wizard and I or when she shouts “It’s me!!” the first time in the tower before she jumps through the window. Yeah, yeah, she’s holding the broom when she jumps across the tower, but she seems to be thinking of the broom as a weapon at that point more than a mode of transport.