The lovestory of cocaine & cigarettes

[psyche]

SWIM's been noticing lately the ego-boost effect of tobacco that comes close to what he assumes cocaine would produce. Tonight when he got high with his brother he found tobacco to have similar effect on his brother; he always feels akward and bothered to smoke weed and be high on my room when our father is home and awake. Weed makes him feel more so. When they got outside to smoke a cigarette, SWIM reminded him that father is on our back and listening us shout. SWIM's brother just laughed and started explaining enthusiastically how little dad would mind him smoking a little on weekends.(I think that is right, but he doesn't beleive it normally)

I know that cigarettes and cocaine have very good synergestic effect and that is because both excert their effect on dopaminergic system, nicotine through nicotinic ACh receptor.
Could someone elaborate on this synergy. Is it somehow more synergistic than any other dopamine-dopamine combo? (I've always thought so for some reason.) Or is the speciality just that those two are took by a fairly fast administration route?
How much do tobacco and cocaine have common in their pharmacological effect?(Meaning the effect the ACh receptor agonism has to dopamine system and the direct effect of cocaine) What's the difference between alcohol's effect on dopamine to that of nicotine's effect on it?