Facing a pandemic-induced plunge in ridership and ticket sales, Caltrain is asking voters in San Francisco, San Mateo and Santa Clara counties for a lifeline this November.\xa0 If approved by a two-thirds majority, Measure RR would impose a one-eighth cent sales tax increase to fund Caltrain\u2019s operations, maintenance and capital projects. Caltrain says that the tax would generate about $100 million annually.\xa0 We\u2019ll break down Measure RR and what\u2019s at stake for the beleaguered commuter railroad.