LOL… I am the opposite of cocky 
(you should have figured it out from my other forum posts and comments reply)
Anyway, Really sorry for the misunderstanding… my apologies. When I read your reply I thought you were gonna go to the actual post of the “Adsense Plugin” and leave a comment (that’s how I support that plugin so my brain naturally assumed it):
WordPress Plugin for Simple Google Adsense Insertion/Integration
Here is why I insist on using the correct forum thread or blog post to reply to queries:
1) Other people in that forum can get easily confused thinking how this topic is relevant.
2) When you post the question/issue in the right forum thread then other people who have the same issue can easily find the solution from your replies.
3) I get hundreds of forum posts/comments/contact form submisstions/emails etc every day. I need to work very efficiently to make sure I can reply to these queries. Having everything organized help me stay efficient.
With that said, here is the answer to your original question:
There are a few ways to do this… just use normal HTML div to center a block and then use the PHP code to output the Ad.
or use something like the following:
<?php
echo '<p style="text-align: center;">';
echo show_ad_camp_1();
echo '</p>';
?>