I suspect you are right. Conservative sites may occasionally be hacked with malware, but they are also listed as "dangerous" sites.
That was the case with Orly Taitz's site, where many Freepers complained of a notice by Google that it was a dangerous site. But google seems to work hand in glove with Obama, so it's not unlikely that they did that for political reasons. I didn't see the warning, possibly because I use google search as my default but do not use google toolbar to search with.
I think Obama has put out a lot of orders for his flunkies to do anything they can to sink the "birther" issue, and that includes blacklisting these sites with danger warnings.
There is nothing named Google allowed on any of my computers and I check my register every week just to make sure. I detest Google. If I use Google, I go through another server.