Jeff from RealJock here. This ad came in through Google Adsense, Google's cost-per-click advertising system. Google's ad system serves ads based on keyword matches. We have no ability to pre-block any ads, but we can block them *after* they show up.
I have gone ahead and blocked this ad from showing up on our site. In our experience, Google takes up to 24 hours to permanently block an ad from our site.
Just so you understand, RealJock is actually running extensive "No on Prop 8" ads on our site for free (we're not making a dime off of them). As the founder of a gay California company (and as someone who is planning on marrying my partner of 12 years soon), I am doing everything I can to prevent the passage of this terrible legislation.
In the future, if an ad that we would obviously never condone (anti-gay in any way) shows up on our site, please do the following:
1. Click on the Help link in the upper right
2. Send an email to our admin. Be sure to include the URL (e.g. http://www.protectmarriage.com in this case) so that we can block it.