Set focus to an input when hovering the assigned label using plain JS. If you need IE8 support, you'll have to include a polyfill for `forEach`.

label-hover-focus.htm

<form>
	<label for="test1" data-hover-focus>Test 1</label>
	<input type="search" id="test1" /><br />
	<label for="test2" data-hover-focus>Test 2</label>
	<input type="search" id="test2" />
</form>
<script>
	var hoverLabels = document.querySelectorAll( 'label[data-hover-focus]' );
	for( var i = 0, len = hoverLabels.length; i < len; i++ ) {
		if( hoverLabels[i].control ) { // make sure this is a label with an assigned input
			['mouseover', 'touchstart'].forEach( function( eventName ) {
					this.addEventListener( eventName, function() { this.control.focus(); }, false );
			}, hoverLabels[i] );
		}
	}
</script>