How to trigger CSS “hover state” using Javascript? [duplicate]

Question

If you could accept using :focus instead of hover, you can use:

var links = document.getElementsByTagName('a');
links[0].focus();

JS Fiddle demo.

Or

var linkToFocus = document.getElementById('link');
linkToFocus.focus();

JS Fiddle demo.

This approach, obviously, requires adapting your CSS to include the a:focus style:

a:link, a:visited {
    background-color: #fff;
}
a:hover, a:focus, a:active {
    background-color: #f00;
}