In javascript date validation, while checking selected date is less than or equal to today’s date, time should be taken into consideration otherwise even when the selected day is equal to today’s date the validation fails.

i.e

 
 var strStartDate          = $("selectedStartDate").val();
 var strStartDateFormatted = new Date(strStartDate);
 var today                 = new Date();
 
 today.setHours(12,0,0,0);

  if(strStartDateFormatted == today)
    console.log("Both are Same");

new Date() will return date with time where as date returned using the datepicker does not contain time so if you directly compare new Date() which comes along with time it would return false even when the date-month-year are equal.

Date.prototype.withoutTime = function () {
    var d = new Date(this);
    d.setHours(0, 0, 0, 0);
    return d;
}

var date1 = new Date(2014,1,1);
new Date().withoutTime() > date1.withoutTime(); // true