Use the control's id and set the top with css. For example (JQuery), let's say you wanted to increase the top of the first name label by 250
var newtop = $('#lblFirstName').position().top + 250;
$('#lblFirstName').css('top', newtop + 'px');
Please keep in mind that ASP will change the lables and you will have to account for that. You would probably be better off applying a common class to the elements you want to adjust and then you could adjust all fields at once by reference the class.
var newtop = $('.adjustabletopclass').position().top + 250;
$('.adjustabletopclass').css('top', newtop + 'px');