Is there any other kind? Recently spammers have been smearing a candidate for president, and some people can't see the forest for the trees.
Maybe you've heard about the spam flying around in support of Ron Paul for President. There are several stories out there that discuss it. For example, Wired has one, and so does the Election Geek blog.
What I find really interesting about the spam and these stories is that people aren't looking at the more logical explanation for the spam - it's a smear campaign in reverse and it works like this: Spam people with a message that asks them to support Ron Paul; people hate spam so naturally they will then develop a dim view of Paul.
And no, this isn't any sort of political endorsement. It's simply an attempt to point out that the thinking of a lot 'spam investigators' is clouded at best.