make input to block and float, Adjust margin top value.
HTML:
<div class="label">
<input type="checkbox" name="test" /> luke..
</div>
CSS:
/*
change margin-top, if your line-height is different.
*/
input[type=checkbox]{
height:18px;
width:18px;
padding:0;
margin-top:5px;
display:block;
float:left;
}
.label{
border:1px solid red;
}