US Web traffic to online gambling sites more than doubled in October as the 2010 World Series of Poker Tournament neared its conclusion, according to data from the comScore Media Metrix service. Meanwhile, humor sites—led by Comedy Central—ranked second, as interest was piqued by Jon Stewart and Stephen Colbert's "Rally to Restore Sanity and/or Fear" in Washington, DC.

• Gambling-Online Gambling sites were the top-gaining category in October, attracting 32.0 million unique visitors, up 141% from the previous month, making it the highest growing site category for the second consecutive month. FullTiltPoker led the category with 4.7 million visitors, up 12% from September, followed by PokerStars with 2.5 million visitors. UB.com drew 1.8 million visitors with its month-long "Perfect Play" promotion. Kingolotto Network came in fourth with 1.7 million visitors (up 23%) followed by Absolute Poker with 1.6 million (up 19%) and Sportingbet PLC with 1.4 million (up 39%).

• Entertainment-Humor sites ranked second, attracting 60.7 million unique visitors in October, up 25% from a month earlier. Comedy Central led the category with 10.8 million visitors, up 26% from September, followed by Break.com with 7.5 million visitors (up 65%) and Cracked with 5.1 million visitors (up 3%). FunnyOrDie was fourth with 4.4 million visitors, followed by CollegeHumor with 4.0 million and FailBlog.org with 3.2 million, both up 16%.

• News/Information-Political sites attracted 27.4 million unique visitors in October as the mid-term elections in the US approached, up 12% from a month earlier. CNN Politics led the category, attracting 7.8 million visitors, up 3%, followed by PoliticsDaily with 5.1 million visitors (up 10%) and RealClearPolitics.com with 3.1 million (up 79%). BarackObama.com was fourth, jumping four spots from its September ranking with 2.1 million visitors, up 221%. The Economist group followed with 2.0 million visitors, while Politico.com reached 1.7 million visitors, up 11%.

comScore also released October data on the top-gaining online properties, led by PartyCity.com, AVG Technologies, and McDonald's:

Looking for great digital marketing data? MarketingProfs reviewed hundreds of research sources to create our most recent Digital Marketing Factbook (May 2010), a 296-page compilation of data and 254 charts, covering email marketing, social media, search engine marketing, e-commerce, and mobile marketing. Also check out The State of Social Media Marketing, a 240-page original research report from MarketingProfs.