This fall MSNBC and CNN viewer stats have plunged 45%. See Alexa's graphic ranking American conservative sites against total US traffic. That could be a plus. On the other hand, Fox was down 21% too.
Canada has a story too. rabble.ca has an alexa traffic rank about ten times that of bloggingtories alexa rank but in the bigger picture of all sites in Canada, Rabble and Blogging Tories are hobby nooks for the dedicated. Go to the link and browse the first couple hundred popular sites in Canada. Google is at the top, the BBC is more popular than almost any Canadian paper, Fulltiltpoker (#225)beats the Financial Post (#226). Politics is not the top interest, not anywhere near the top interest for Canadians and anything either left or right is hard to find. This tells me that a successful party must appeal to people with more important things to do. You don't wean them from the other team, you draw them from the otherwise engaged.
Footnote: The Liberal party web site (2800 in Canada) and the Conservative web site (14,000 in Canada). The NDP party (15000 in Canada). The Green Party (11000 in Canada). Obviously site traffic is different from votes. Why do the sites have different levels of engagement?