Question about why this code doesn't work

Question about why this code doesn't work

It's just a simple "mouseenter / fadeto" function. Basically I want my button to dim when the mouse enters the div. So the code is thus:

$(document).ready(function() {
    $('#createProfileButton').mouseenter(function() {
        $('#createProfileButton').fadeTo('fast', 0.25)    
    });
});

I'm fairly new to JQuery but I've done Java so I don't know where it's going wrong.