I can vouch for the popularity of blogging about big sporting events. I have an autoblog i set up covering the subject of the 2010 World Cup and my adsense earnings from May 2010 alone from this site with minimal SEO work is £168 (approx. $250).
Lifetime earnings from this blog since its inception in Dec 2009 is £500 (approx. $750).
This month to date it is sitting at £75 ($120) and we are only a quarter through the month. I also earn quite well on Amazon from these types of sites. Yikes, did i give a business model away here?!?!
Needless to say i cover as many sporting events as i can and my World Cup 2014 is already prepped ready to go lol!
Just remember that this is all set up as an autoblog with minimal SEO work, approx. 30 minutes at its inception and nothing since. It seems that the popularity of the event adds drive to the site, allowing it to gain Google ranking seemingly on the surge of popularity for the event itself. My World Cup site is proof of this...as are others i have.
I hope this helps some Warriors trying to make their first buck(s) online.