On hover text change of button

HTML:
<a href="#" onmouseover="mOver(this)" onmouseout="mOut(this)" >Hover me</a>
CSS:
a {
    background-color: orange;
    display: inline-block;
    padding: 20px 20px;
    text-decoration: none;
    color: #fff;
    text-transform: uppercase;
    font-size: 25px;
    transition: 0.4s all;
    width: 180px;
    height: 30px;
    text-align: center;
}

a:hover {
    background: blue;
}
JS:
function mOver( obj ){
	obj.innerHTML = "Go...!"
}
function mOut( obj ){
	obj.innerHTML = "Hover me"
}