I am using NodeJS to create a server that brings in serial data. The serial data is successfully showing in the HTML; however, I would like to create a 'var' that can hold the data. Please can someone help?

Here is my index.html page:

<!DOCTYPE html>
	<script src="/socket.io/socket.io.js"></script>
	<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.6.2/jquery.min.js"></script>
		// open a connection to the serial server:
		var socket = io.connect('http://localhost:8080');

		 // when you get a serialdata event, do this:
		socket.on('serialEvent', function (data) {
			// look for the textDisplay element in the HTML below:
			var element = document.getElementById('IDTag');
			// set the stuff inside the element's HTML tags to
			// whatever the 'value' property of the received data is:
			element.innerHTML = data.value;


	And the latest is:
	<div id="IDTag">The RFID Tag ID will show here.</div>	
and here is my SerialServer.js doc:

	a node.js app to read serial strings and send them to webSocket clients
		* node.js (http://nodejs.org/)
		* express.js (http://expressjs.com/)
		* socket.io (http://socket.io/#how-to-use)
		* serialport.js (https://github.com/voodootikigod/node-serialport)
	based on the core examples for socket.io and serialport.js
	created 21 Aug 2012
	modified 14 Oct 2012
	by Tom Igoe
	Patches and improvements suggested by Steve Klise, Lia Martinez, and Will Jennings


var serialport = require("serialport"),				// include the serialport library
	SerialPort  = serialport.SerialPort,			// make a local instance of serial
	app = require('express')(),						// start Express framework
  	server = require('http').createServer(app),		// start an HTTP server
  	io = require('socket.io').listen(server);		// filter the server using socket.io

var serialData = {};								// object to hold what goes out to the client

server.listen(8080);								// listen for incoming requests on the server

console.log("Listening for new clients on port 8080");

// open the serial port. Change the name to the name of your port, just like in Processing and Arduino:
var myPort = new SerialPort("/dev/tty.usbmodemfa131", { 
	// look for return and newline at the end of each data packet:
	parser: serialport.parsers.readline("\r\n") 
// respond to web GET requests with the index.html page:
app.get('/', function (request, response) {
  response.sendfile(__dirname + '/index.html');

// listen for new socket.io connections:
io.sockets.on('connection', function (socket) {
	// if there's a socket client, listen for new serial data:  
	myPort.on('data', function (data) {
		// set the value property of scores to the serial string:
		serialData.value = data;
		// for debugging, you should see this in Terminal:
		// send a serial event to the web client with the data:
		socket.emit('serialEvent', serialData);
Thanks in advance!