[jQuery] nod names in from fields id

[bob]

Hi,
How do i get nod names in for loop based on fields id?

var serverVals = {
        'firstName':'John', //
        'city':'NY',
        'state':6,
        'gender':1,
};

<input type="text" name="firstName" id="firstName">

<select id="state" name="state">
        <option value='AL'>Alabama</option>
        <option value='AK'>Alaska</option>

<input type="radio" name="gender" id="gender1" value="1" />Male
<input type="radio" name="gender" id="gender2" value="2" />Female


for(var i in serverVals){
        alert(jq('#'+i).nodeName); ??? undefined
//I would like to get
text
radio
...
}