Converting Strings to MovieClips

I am creating a map that highlights certain states relative to the person selected. The movieclip that needs to be highlighted is in the XML with other information.
My Problem:I am trying to pull out a variable in my XML that is actually a movieclip directory to put into my TweenLite. I can trace the directory, i.e. enfFrame_mc.missouri_mc, but when I try to pull it out it is a string and will not convert. Any one have any tips on how to do this a snippet of code is below:


var colorState:String; 
        
colorState = String(xmlData.pic.hmstate[targetThumbs]);
        
trace(colorState);
        
 TweenFilterLite.to(colorState, 1, {type:"Color", colorize:0x3366ff, amount:1});