The mediaelements.js documentation tells you how you can do this without jQuery:
<script>
// JavaScript object for later use
var player = new MediaElementPlayer('#player',/* Options */);
// ... more code ...
player.pause();
player.setSrc('mynewfile.mp4');
player.play();
</script>
In your case, you'd do something like this:
<script>
// JavaScript object for later use
var player = new MediaElementPlayer('#video', {
defaultVideoWidth: 480,
defaultVideoHeight: 270,
features: ['playpause','progress'],
});
</script>