It was after 1 a.m. when Mark Kelly approached the lectern to address a small crowd of cheering supporters in Tucson on Election Night 2020. The former astronaut and retired Navy captain had just toppled Sen. Martha McSally to flip a seat vital to Democrats' efforts to wrest Senate control from Republicans. And for the first time in 70 years, the Democratic Party held both of Arizona's upper chamber seats.In his remarks that night, Kelly invoked John McCain's legacy and pledged to try to live up to his reputation as a maverick with a backbone of steel - a lawmaker who was willing to stand up...
