U.S. Vice-President Kamala Harris has emerged as the clear frontrunner to be the Democrats' nominee for the 2024 presidential election, just one day after President Joe Biden dropped out of the race and endorsed her. Jackson Proskow reports on the growing number of Democrats endorsing Harris, whether any other Democrats have a viable chance of challenging her; the flood of donations pouring in; and how this has thrown a curveball into Donald Trump's campaign.