function silverpopGetCookie(name) {
    var prefix = name + "=";
    var cookieStartIndex = document.cookie.indexOf(prefix);
    if (cookieStartIndex == -1)
                return null;
    var cookieEndIndex = document.cookie.indexOf(";", cookieStartIndex + prefix.length);
    if (cookieEndIndex == -1)
                cookieEndIndex = document.cookie.length;
    return unescape(document.cookie.substring(cookieStartIndex + prefix.length, cookieEndIndex));
}
 
<!--
function silverpopSetCookie(cookieName,cookieValue,nDays) {
	var today = new Date();
	var expire = new Date();
	if (nDays==null || nDays==0) nDays=1;
	expire.setTime(today.getTime() + 3600000*24*nDays);
	document.cookie = cookieName+"="+escape(cookieValue)
	                + ";expires="+expire.toGMTString() + ";path=/; domain=legalzoom.com";

}
//-->
 
//This splits the queystring and will get the values for the strings
function silverpopGetQueryVariable(variable) {
	var query = window.location.search.substring(1);
	var vars = query.split("&");
	for (var i=0;i<vars.length;i++) {
	  var pair = vars[i].split("=");
	  if (pair[0] == variable) {
	    return pair[1];
    }
  } 
}

<!-- 
  // silverpopSetCookie('m', silverpopGetQueryVariable("spMailingID"), 30);
  // silverpopSetCookie('r', silverpopGetQueryVariable("spUserID"), 30);
  // silverpopSetCookie('j', silverpopGetQueryVariable("spJobID"), 30);
  
   sURL = document.location.toString();
   if(sURL.indexOf("spMailingID") > 0)
   	silverpopSetCookie('mrj', silverpopGetQueryVariable("spMailingID") + '|' + silverpopGetQueryVariable("spUserID") + '|' + silverpopGetQueryVariable("spJobID"), 30); 
//-->