You can in fact have any sites approved on the Adsense program, provided that site has enough traffic going through. Adsense's primary concern is the ability of your website to generate traffic, as their business model is based on this entirely. Of course, your website will also have to adhere to their TOS before being approved/accepted into their program. If you can proof that your site has good enough traffic, by providing traffic stats, etc, when requested, then that should increase your chances of getting accepted into their program.
Personally, I find integrating Adsense code into Blogger is much simpler. Furthermore, Blogger has better leniency as compared to Wordpress, which has placed so many restrictions on their platform. Unless if you host your own Wordpress blog, then that is different entirely, as a whole.