I tried this: http://jsfiddle.net/ilyaD/KGcC3/
HTML:
if the options are static, you could listen for the change event on your select box and add padding for each individual item
$('#id').change(function() {
var select = $('#id');
var val = $(this).val();
switch(val) {
case 'ValOne':
select.css('padding-left', '30px');
break;
case 'ValTwoLonger':
select.css('padding-left', '20px');
break;
default:
return;
}
});