Drop this code on a splash page that links to your landing pages to append your tracking parameters.

pass_params_to_links.js

$(document).ready(function(){
	// Grab querystrings
	var querystring = window.location.href.slice(window.location.href.indexOf('?') + 1);
	// Append the above to each link on our page so we maintain utm params etc
	$('a').each(function()
	{
	    var href = $(this).attr('href');
	    if(href) {
	        href += (href.match(/\?/) ? '&' : '?') + querystring;
	        $(this).attr('href', href);
	    }
	});
});