Lyric discussion by diabolusmagus 

Cover art for Proud Mary lyrics by Creedence Clearwater Revival

I think it's hilarious that chris4420 found a quote about CCR (and John Fogerty specifically) being ANTI-DRUGS, and claims it's proof that this specific song is about smoking dope.

That's along the same line as interpreting the song from one or two words... taking a quote entirely out of context because it mentions Fogerty "dabbling with marijuana," completely ignoring the immediate follow-up, "but that was as far as it ever went."