I have a search program that returns an HTML string which I display to
the user. I want to highlight the search terms. However a simple
search and replace on the HTML causes problems.

If the user searches on Georgia and I get back this:
<div style="font-name:Arial">Georgia, Alabama, and Louisiana</div>

It works fine:
<div style="font-name:Arial"><span style="background-
color:yellow;">Georgia</span>, Alabama, and Louisiana</div>

However if the HTML that comes back is this:
<div style="font-name:Georgia">Georgia, Alabama, and Louisiana</div>

I get a serious problem which breaks the formatting and looks
terrible:
<div style="font-name:<span style="background-color:yellow;">Georgia</
span>"><span style="background-color:yellow;">Georgia</span>, Alabama,
and Louisiana</div>

The HTML I'm getting back is quite complex, with nested spans, style
tags, etc. I'm stuck for how to solve this problem - is there a
regular expression I can use to match chunks of non-formatting text to
replace? I have neither the time nor the resources to write a full
blown html tokenizer.