Tracking last_touch with UTM params

utm_params_last_touch.html

<script type="text/javascript">
  function getQueryParam(url, param) { 
    param = param.replace(/[\[]/, "\\\[").replace(/[\]]/, "\\\]"); 
    var regexS = "[\\?&]" + param + "=([^&#]*)", 
    regex = new RegExp(regexS), 
    results = regex.exec(url); 
    if (results === null || (results && typeof(results[1]) !== 'string' && results[1].length)) { 
      return ''; 
    } else { 
      return decodeURIComponent(results[1]).replace(/\+/g, ' '); 
    } 
  };
  
  function campaignParams() { 
    var campaign_keywords = 'utm_source,utm_medium,utm_campaign,utm_content,utm_term'.split(',');
    var kw = '';
    var params = {};
    var index; 
    for (index = 0; index < campaign_keywords.length; ++index) { 
      kw = getQueryParam(document.URL, campaign_keywords[index]); 
      if (kw.length) params[campaign_keywords[index] + ' [last touch]'] = kw;
    }
  
    analytics.identify(params);
  }
</script>