here is your code working jsfiddle .Refer the fiddle. Include jquery:
<script src="//code.jquery.com/jquery-1.11.0.min.js"></script>
<link href="http://localhost/mytests/js/select2.css" rel="stylesheet"/>
<script src="http://localhost/mytests/js/select2.js">
$("#e1").select2();
$("#e1").select2(
{
placeholder: "Select a State",
allowClear: true
});
$("#e2_2").select2(
{
placeholder: "Select a State"
});