How to return non-XML text from an ASP script?

My HTML5 Canvas needs to check for user authentication, so it queries an asp script for a session status result (just a simple string).  But I am not able to get it to work.  I have created a simple testing asp script:

<%
response.write "GOT_HERE" 
%>

I can confirm this script returns 'GOT_HERE' to the screen when loaded directly in the browser.

I attempt to query it in my canvas via:

$('#dom_overlay_container').on('click', '#button1', function() {
			
			this.myDynText.text = "Step 1";
				
			  var xhttp = new XMLHttpRequest();
		
			  xhttp.onreadystatechange = function() {
				  this.myDynText.text = "Step 2";				  
				  if (this.readyState == 4 ) {
					this.myDynText.text = this.responseText;					
				}
			  };
			  xhttp.open("GET", "TEST.asp", true);
			  xhttp.send();
			
		}.bind(_this));

I successfully get to Step 1, but not Step 2.  Any idea what's wrong?

Thanks,
Geoff