Edit in JSFiddle

<h4><center>Some JSON testing</center></h4>

APIKEY: <input id="apikey" type="text" style="width:80%" name="apikey" value="4881f4aa3ba849a08db01dc65863ccb6"/><br/><br/>
<input id="test" type="button" style="width:90px;"  name="test" value="Test" />
<hr/>

<script id="template" type="text/x-jquery-tmpl">
    <b>Amendment ID: ${amendment_id}</b><br/>
    Sponsor: <a href="http://bioguide.congress.gov/scripts/biodisplay.pl?index=${sponsor_id}" target="_blank">
    ${sponsor.title} ${sponsor.first_name} ${sponsor.last_name}</a>
    (${sponsor.party}-${sponsor.state})<br/>
    <hr/>
</script>

<div id="info"></div>

var basepath = "http://api.realtimecongress.org/api/v1/amendments.json"; 

$("#test").click(function(){
        var url =basepath  + "?apikey=" + 
        $("#apikey").val() + "&callback=?";
    //console.log($("#apikey").val());
    //console.log(url);
    $.getJSON(url,function(data){
        //console.log(data);
        $("#template").tmpl(data.amendments).appendTo("#info");   
    });
    
    /*
    $.ajax({
        url: basepath  + "?apikey=" + $("#apikey").val(),
        dataType: "jsonp",
        cache: true,
        success: function(data) {
            //console.log(data);
            $("#template").tmpl(data.amendments).appendTo("#info");
        }
    });
    */
});