by Google Books; it seems to be over a fifth of the total. Presumably when it's your own work you have a better impression of quite how long the excerpt is relative to the total.
If you haven't read For Love and Money but would be interested in seeing the introduction and an explanation of how romance novels can be written in a variety of literary modes, you can now do so for free.
While I'm on the topic of Google Books, I may as well mention that page 352 of the tenth edition of A Glossary of Literary Terms includes the following about romance novels:
The history and analysis of this novelistic form has increasingly become the subject of scholarly investigation; it now has its own literary periodical, the Journal of Popular Romance Studies, begun in 2010. Refer to Carol Thurston, The Romance Revolution (1987); and Pamela Regis, A Natural History of the Romance Novel (2003).I'm pleased to see that JPRS is beginning to beginning to be more widely known and I'm also pleased (and very intrigued) by the fact that the Glossary has chosen to highlight Pam Regis and Carol Thurston's studies of the romance. I wonder if we can take it as a sign that at long last Janice Radway's Reading the Romance has lost its preeminent position.