This was the first solution, when the question was different.
It's trivial using jQuery: when user clicks on your radio/star you submit the form.
$(".star").click(function() {
//your logic on star click
$("#ratethecommand").submit();
});
You can also change your actual filosofy, doing a simple redirect instead of sumbitting the form: in this case you should transform your actual radio inputs (the stars) to A elements pointing to your controller/action and having the value as parameter (better if integer):
<a href="@Url.Action("rated/3", "Rating")">icon of your star</a>
If you have default routing then you can retrieve rate from id in your action (by the way: capitalize it!).
One last idea: you can also choose the asynchronous way, again with jQuery post and get methods it will be easy to implement!
Final solution (answer to last question edit)
Remove INPUT elements from A elements content. Insted put text / icons of stars.
Hope this helps,
Alberto