If you just want to see the route in Google Maps, *and* you have a publicly-accessible web site where you can store the GPX file, simply enter the GPX file's URL path in the Google Maps search box. For example:

http://maps.google.com/maps?f=q&sour...,0.948257&z=11

If you don't have write access to a publicly-available web server, you might be able to use something like Google Docs, but I haven't tried that yet.