Harris readies a Philadelphia rally to introduce her running mate. But her pick is still unknown

Vice President Kamala Harris will introduce her new running mate at a Tuesday evening rally in Philadelphia. But with the event mere hours away, her choice wasn't yet publicly known. In recent days, Harris has zeroed in on a trio of potential finalists: Pennsylvania Gov. Josh Shapiro, Arizona Sen. Mark Kelly and Minnesota Gov. Tim Walz. After their Pennsylvania debut, Harris and her new running mate plan visits together throughout the week to key battleground states. Republican Donald Trump also created suspense by holding off on making his choice of a running mate — Ohio Sen. JD Vance — until last month's Republican National Convention.