WP_Query orderby not working on custom post_type

OK, I figured it pour reading about Orderby Parameters in WP_Query more carefully. I needed to set votes to meta_key and orderby to meta_value_num:

$args = array(
        'post_type' => 'entry',
        'meta_key' => 'votes',
        'orderby' => 'meta_value_num',
        'order' => 'DESC',
        'posts_per_page' => 10,
        'post_status' => 'publish'
    );
$loop = new WP_Query($args);