div#wrapper { width: 950px; }
div#wrapper div#leftcol { 
float: left; width: 215px; position: relative; 
}
div#wrapper div#midcol { width: 547px; float: right; position: relative; }
div#wrapper div#rightcol { width: 125px; float: right; position: relative; }
div#wrapper div#rightcol div#3rdPartyAds { width: 125px; float: right; position: relative; }