At their core, politics relate to 'people' and 'society'. I.e.: they are 'social' issues -- not exactly the stereotypical nerd's forte. As a geeky kind of person myself, I know we can "get by" and figure many things out using logical language, but I'd say we're generally "behind the curve" in understanding what makes the average person tick. Thus when things get so bad that the nerds start focusing on politics, I see it as an ominous indicator of desperate times ahead.
It's likely other ominous indicators of desperate times ahead that cause the nerds to focus on politics. Things like out-of-control debt, out-of-control spending and huge swathes of people who should be being productive in a healthy economy living off the government dime (read leeching off people who *are* productive).
And who is to say a nerd cannot also be involved with politics? The generation that's starting to get into their college years were born with technology, every last one of them, and most have been using the internet since they were children. A nerd who was around a ways before then would be much more in-tune with his nerdy side (is that a thing?) than politics. But I agree, it's more important to be involved in what's going on with politics now than ever before, as there are so many happenings nowadays that would make even the most average of Joe's say "Wait a minute, something's not right here."
Not to say the Internet hasn't helped people escape the "Channel X" news squad, "Feeding you what you want to hear and nothing else."
