request = 'http://ws.geonames.org/findNearbyPostalCodesJSON?postalcode=' + postalcode + '&country=' + country + '&radius=0&callback=getLocation';
we are able to extract the state abbreviation using:
var txtState = document.getElementById("txtState");
txtState.value = postalcodes.adminCode1;
Cheers to anyone who needed that info!