[Chalky] That's more or less the etymology I've heard as well, from no less eminent a source than Bill Bryson (Made In America). "caucii" seems an unlikely plural since "caucus" isn't of Latin origin... All the same though, the one thing I do know is that the real trick with spelling the plural of "caucus" is knowing when to stop.
Simple - the plural of caucus is caucuses. That's from the lexicon I keep here in the shack - The New Penguin E.D. - etym. 'probably of Algonquian origin'. Algonquians being of east coast American peoples; ergo - N.Y slang! ... ;-)
At 0500 hours I get a craving for chips with lots of vinegar? I'm the wrong genda to be pregnant. Maybe if I get a sex change the cravings will be justified????