I believe the profit you will make is $6,000 and not $4,000. 33 out of 37 times you will be up $6,000 and 4 out of 37 times you will be down $66,000.
Answering your original question, it is possible to get rich in a casino playing any game in any way. No one is stopping anyone from placing $25k on a single number and winning $875k.
Is your idea great? If you don't have $70k your idea may seem amazing. Once you actually have a lot of money, you won't consider this. Every bet costs you 2.7% of your initial wager in the long run. The more money you have, the more you should invest properly. That's pretty much it.