sure, if the blog have traffic, it's all the traffic factor, the rest doesn't count so much (position, color of ads, etc...)
After making blog and adding various ppc links you must try for developing your blog and ensure that you must get good traffic. Good traffic of your blog means more people attract to your blog.
What I do is first make the blog have very little ads so the site looks very attractive and gets a good amount of traffic, then I add a few more ads once the traffic is consistent and going strong.