Can you truly make money blogging? Sure, but the better question becomes is the pay worth the required time?
Many paying blogging sites earn money through Google's Adsense. They also require their writers to spend hours every day posting responses on similar blogs in order to get their name out there... Though that doesn't officially qualify as SPAM, it certainly seems it. Blogging for money can be cut throat, but at the same time becoming cut throat and being in it only for the money takes a lot of the joy away.
If you have hours to spend, certainly look into it, but be careful. While it can sound easy, you may find the time you are putting in does not become worthwhile when you receive a paycheck for less than $10 after investing 2 or 3 hours a day over a month's span. $10 for 60 hours of time is absurd!