Detroit Mayor Mike Duggan declined an initial allocation of the newly authorized Johnson & Johnson Covid-19 vaccine this week even as nationwide demand continues to outpace available supply. Duggan, a Democrat who has been mayor since 2014, said he turned down the shipment because the city is able to meet current demand with its supply of the Pfizer/BioNTech and Moderna vaccines -- even as his administration expanded vaccine eligibility Thursday to residents ages 50 and older with chronic medical conditions.