Political sites see huge growth

But will the pre-election bump last, especially among liberals?

Two reports out this week showed just how much U.S. voters have turned to independent political blogs to read and express news and views.

A comScore report revealed that political sites such as HuffingtonPost and Politico have seen traffic surging during.

Huffington Post had the most traffic in September and some of the strongest growth, with unique visitors rising nearly six-fold from a year earlier to 4.5 million. Politico.com saw its uniques climb 344% to 2.4 million.

Both sites use a mix of staff writers, paid freelancers and guest contributors to produce content.

The Drudge Report, RealClearPolitics.com and Free Republic.com round out the top five list.

The demographic profile of visitors to these political sites skews older, wealthier and more male than the general Internet population. 

And according to a separate report from the Pew Research Center, liberal Democrats are the most avid readers of political blogs. 

The report revealed that 43% of liberal Democrats read blogs, more than twice the figure for conservative Republicans and also a significantly higher percentage than among independents or moderates of either party.

Supporters of Barack Obama have also been more engaged in offline political activities this year, through donations and attending events, than have backers of John McCain, the report said.

In an interesting preview of what might happen after the election, 37% of liberal Democrats who support Obama also say they would be angry if their candidate lost, double the percentage of McCain supporters who feel that way about an Obama win.

Anger usually leads to action, both online and off, which suggests that traffic to these blogs would continue to grow at a fast rate should Obama lose.

But the most recent polls are pointing to a victory by the senator from Illinois. So does that mean the liberal Democrats who are now flocking to these sites will take a break once the election is over?

My guess is not right away, certainly not through the honeymoon period that usually persists for several months after a new president takes office.

But if the economic downturn gets bad enough, and Obama fails to make a difference, there's always a chance that some of the heaviest users of these sites -- liberal Democrats -- will start to tune out.

That will take months or maybe even a year to play out. For now, what's certain is that it's a great season for political sites.