Var issues

I am trying to make a MC via the var command so that if one page is already open my if command will check it on a button call to action so that it does not do the same thing twice, but for some reason in AS3 the below sets of code always bring back errors and I have no idea why.

This is in my first frame as AS

var stageSet:MovieClip = blank;

This is in a button call to action CLICK

stageSet = contact;

They always bring back this
1120: Access of undefined property blank.
1120: Access of undefined property contact.

I tried placing the varMC on both my root and inside an MC and both times same error. Does anyone have a work around or know what is going on?

I am drawing blanks and could really use some help.