However, in my personal experience (a long lesson to learn!), it's a bit like Field of Dreams thinking: "if you built it, they will come." That does work, but it's a long process, and I suspect it's generally a side effect of the blog.
Think about it this way: is your ideal client really going to be spending a lot of their time reading blogs like yours? I would guess not; the people who would likely read it would be other technical people.
When I went from Field of Dreams thinking to direct line to profit thinking, I was amazed at how much work I was doing that had no chance of yielding income. I discovered I was only doing profit-generating things for about 2 hours per day. I thought I was busy and going to be successful, but I was just wasting my time.
HTH. Good luck to you. I think you definitely can make that much money per month in income, but make sure you have a definite value prop.
FWIW, when I was doing blog/email marketing/web design work, I found the best path was thus. Get them to sign up for a webinar on your blog, and give a live webinar via GoToMeeting once a week. That was my best success -- I think the key was that it qualified leads a ton, and gave me a chance to exhibit my professionalism and skillset before I asked for money.