Chicagoans have been asking themselves a lot of unusual questions lately.

Is Mayor Rahm Emanuel’s reelection campaign unraveling at the prospect of a challenge from Chicago Teachers Union (CTU) President Karen Lewis? Could the groundswell of support for the 2012 CTU strike be revived through a Lewis campaign for mayor, boost the fortunes of a clutch of independent candidates for city council, and build a movement for social justice? What does it mean to run a genuinely pro-worker, labor-based political campaign for mayor of the country’s third largest city?

Not long ago, such propositions would have seemed absurd.