How do you enable ASP.Net MVC client validation for Kendo UI DropDownList and ComboBox?

Based on a response on the Kendo forums, the reason the validation does not work is because jquery validate does not validate hidden fields by default. The easiest way to change that is to use the $.validate.setDefaults method to override that behavior like so:

$.validator.setDefaults({
    ignore: ""
});

This still does not add the "input-validation-error" class to the combo box or drop down, but at least it adds the validation error, and keeps the form from being submitted.