function vote(url)
{
  var width  = 310;
  var height = 240;
  var left   = Math.floor( (screen.width - width) / 2);
  var top    = Math.floor( (screen.height - height) / 2);
  var params = "top=" + top + ",left=" + left + ",height=" + height + ",width=" + width + ",scrollbars=no";

  window.open(url,"",params);

}