The percentage of individuals who prefer a certain body type, such as a "fat dude," can vary widely based on many factors, including cultural background, personal preferences, and individual experiences. There's no specific data point that directly answers your question. If you are looking for a general understanding of body preferences or attraction, surveys and studies could provide some insights, but they would not definitively state a percentage for any specific group of 4 million girls.
If you have a more specific context or demographic in mind, it may help to refine the question further.