It was Rick Perry - not Romney.
https://www.google.com/search?num=30&site=&source=hp&q=rick+perry+offensive+rock&oq=rick+perry+offensive+rock&gs_l=hp.3..0i22i30.4857053.4863224.0.4863989.25.17.0.8.8.0.157.1392.9j5.14.0....0...1c.1.27.hp..3.22.1672.7lGCNmHCF3w
Thanks for the correction!