Firstly, let's define democracy for a moment - the word originally meant "rule of the people" (thanks, wikipedia.) Also from that article, you might be interested to know that the original democratic process involved randomly selecting citizens for the jobs and other citizens voting. Note that citizens here means "People who would be obligated to fight if war broke out" and thus excluded women and children.
Contrast that with what we have: Something between a meritocracy and an aristocracy, where people vote for the rich person with the smoothest tongue or the best PR campaign. (Dispute all you like - the number of rich politicians far outweigh the poor politicians)
Now the historical definition is not a canonical answer - after all, meanings change - but the spirit of the idea, that we mere citizens can shape our laws and the ethos of our country, remains in the word. Given the perpetual and increasing apathy at the poll booths, this idea is clearly no longer pervasive.
While we're being linguistically pedantic, my first association - and I hope I'm not alone - when faced with the term "online anarchist groups" was Lulzsec, Anonymous and other similar groups. While I'm not certain of the definition, I'm not sure these organisations fit the bill - they don't seem hell-bent on destroying government, merely highlighting their corruption and hoping to inspire or force others to bring responsible individuals to justice. At least that's my reading of the situation.
I think that concludes my answer. If my reading of the ethos and the question are correct, the aim is certainly there. I haven't touched on the biases within these organisations, or whether their subversions make them an ad-hoc ruling class, but for now, at this level, if their ethos and aims are in any way effective at attacking hypocrisy and corruption, it's hard to reject the statement that they are helping democracy, at least for now. The end result, whether they ultimately save democracy or just become a disruptive meritocracy is anyone's guess.