Vice President Kamala Harris will hold her first rally with her new vice-presidential nominee on Tuesday in Philadelphia, sources say. The location suggests that Pennsylvania Governor Josh Shapiro has moved to the top of a short list of running mates and that the Harris campaign has decided that the state that Democrats won back from Republicans in 2020 is a must-win once again. A campaign aide told Reuters on Tuesday not to read too much into the choice of the first city of a weeklong battleground state tour. The tour will take four days and cover multiple states, the aide said. The high-stak…