I'd say the best you can hope for is there being someone in line who's only looking to buy one ticket. Beyond that, I'd say you'd probably have to get two rush tickets and try to buy the third somewhere else in the theater and catch up at intermission. I have the same problem when both my parents come to visit me in the city (usually only my mom comes).
Good luck!
Oh, or you could try (even though you'd have to get there really early) Color Purple. Don't they have a general rush??
But when did New Hampshire become--Such a backward wasteland of seatbelt hating crazies?...I mean, only 40 people actually live there. The others are just visitors who come for the tax-free liquor and three inches of novelty coastline. John Hodgeman on The Daily Show (1-30-07)