<input type="text" id="demo-input-prevent-duplicates" name="targ_country" />
 <script type="text/javascript">
    $(document).ready(function() {
        var host = window.location.protocol+"//"+window.location.hostname;
        jQuery("#demo-input-prevent-duplicates").tokenInput(host+"/forms/campaign_location.php?action=country", {
        preventDuplicates: true,
        theme: "facebook",
        crossDomain: true
    });
    });
</script>

<?php
if( isset( $_GET['action'] ) && isset( $_GET['q'] ) ) {

    $search = $db->clean( $_GET['q'] );
    $query = sprintf("SELECT CountryId, Country from countries WHERE Country LIKE '%%%s%%' ORDER BY Country DESC LIMIT 10", mysql_real_escape_string($_GET["q"]));
    $result = array();
    $rs = mysql_query($query) or die( mysql_error() );

    while( $row = mysql_fetch_object( $rs ) ) {
        $result[] = $row;
    }

    # JSON-encode the response
    $json_response = json_encode($result);

    if($_GET["callback"]) {
        $json_response = $_GET["callback"] . "(" . $json_response . ")";
    }
    echo $json_response;
}
?>

propertyToSearch: "Country"