JQuery :: Set Of Radio Inputs On A Form?

I have a set of radio inputs on a form. These are bound to some values in a database. They are to indicate preferences of the user. So i may have 10 items in the list and i want the user to tell me the one they prefer. So when the list loads the first time all of the radios are not selected. They select one then hit save. I persist this value to the database and the next time they come back i want to fill that radio button in.

I'm having an issue doing this. It seems to me like: you can load a list of radios that are all unselected. you can select a single one of these you cannot select one and then unselect it so that none are selected

My problem is that i load the list then i loop over each of the elements and use the id to look for a saved preference value. If i find one then i want it selected in the radio. If not then don't select it. What I'm getting is the last item in the list always being selected in the radio

<td>
<input id="contactPrimary_Address_<#= _contact.Addresses[a].AddressGuid #>" type="radio" class="contactPrimaryPref" name="addressPrimary" checked="false">
</td>
$(".contactPrimaryPref").each(function(n) {

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