Gov. Chris Christie famously derided residents of our area as “Communists from Montclair.” If you’re the least bit left leaning (with a sense of humor), you’ll love the “Last Supper,” a musical farce playing at SOPAC until August 7. The plot centers around five liberal-minded grad students, living in a conservative part of the country, who try to understand their neighbors by inviting them to dinner. Things don’t go as planned. The performance starts off on a high note with the dinner hosts singing “Tonight We Save the World” a funny ode to their idealistic mindset. The strength of this musica…