Find text of html element, replace with modified text

newText.js

function newText(obj, text, classy) {
     var hLen = text.length,
         firstIdx = text.indexOf(' '),
         startStr = text.slice(0, firstIdx),
         endStr = text.slice(firstIdx, hLen),
         newStr = startStr + '<span class="'+classy+'">' + endStr + '</span>';
         $(obj).html(newStr);
}