How do two forms based off of almost same .aspx?

I'm trying to figure out the best way to accomplish this. I have a need for two pages that are very similar, but bind to different database tables. I want the user to see abc.aspx and def.aspx as separate urls, but get mostly the same page (defined as unique by a hidden field and a few label differences). The code behind is almost the same, just a couple things that will vary based on the hidden field.
What is the best way to do this? I'm trying to avoid the obvious solution of making two copies of the .aspx and code behind pages. I'm hoping I can just vary what I need to in the Page_Load method.


thanks for the suggestions. 
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