function processSubscribe(){
        
    email_string = $("#registered_email_email").attr("value");
    csrf_string = $("#registered_email__csrf_token").attr("value");
    
    //ajax request do subscribe
    $.get('/subscribe', {email: email_string, _csrf_token: csrf_string}, function(data) {
        
        //update the html
        $("#subscribe_cta").replaceWith(data);
        
    });
        
}