If you write five posts the first day, write five every day. Blogs are all about consistency, and the rate of posting, not an "X value" for total posts – at least, if your primary concern is profit.
If you're happy to game the search engines and play at black and grey hat SEO tactics, you could easily become profitable in short order… say 1 post every 2-3 days for 3 months, dominance in some profitable adwords keywords, and then the inevitable "domain flip", where you cash in on your traffic and commissions papertrail by getting some sucker looking for a shortcut to buy you out.
If you want to write genuinely from your heart on a topic of interest… Well, that's a lot harder. You need to be just as disciplined as the SEO, but also remain focused and push that content out to schedule. It's rough! But, if you can do it, and enough people like what you write, you may find yourself a few retweets away from a substantial amount of regular traffic, and adwords checks rolling in to the tune of $25-100 a month inside a year for that same post-every-other-day style blog. You want to scale up the dollars, scale up your output, and keep your niche(s) focused, just work on more of them. For me, it might be IT management issues, parenting, japanese manga, cooking, and hoopdancing for men.
Even then, if I can nail a post a day across each of those, we're talking maybe breaking 10K a year. Still, just for writing? Not too bad… And if I start a "Daddy Fitness and Cooking Bootcamp", maybe that doubles again. Maybe I get on TV. Maybe there's eventually enough content (and publisher name recognition) for a book deal. And so on, and so on.
Anyway, the point is simple: start writing, keep writing. That's the only thing. You'll be surprised at how quickly you hit 100 posts, and then 500 (heck, I'm over 500 answers on Quora, and it seems like I just crested 100 not too long ago…).
If you have perseverance, you won't need much luck – but I wish you the best of both all the same.