Wouldn't just deleting (or replacing by nothing) all the '<div style="margin-top: 1em"/>'s work?
(The above's the quickest solution, while the 'better' solution would be to replace things such that you had '<p>Blah blah blah, paragraph 1.</p>', etc, then to style that in the header, e.g.
Code:
<head>
<style type="text/css">
p { text-indent: 1.5em; margin-top: 0; margin-bottom: 0}
</style>
</head>