It's one of those complicated questions. The early successes of Maharashtra grew out of the successes of Bombay State. (Maharashtra was only created in 1960.) It was easier to do because there was already an industrial mentality and an entrepreneurial spirit among the people.
Compare this to, say, Bihar, where there was no legacy to build on and no history of great entrepreneurial vision.
So yes, I do give credit to Maharashtra's politicians. But it's not as simple as you seem to think.