5 major questions facing Kamala Harris now

Few candidates have had as successful a campaign launch as Vice President Kamala Harris, raising hundreds of millions, moving up in polls and energizing the base. The Harris campaign notched an additional $36 million in the 24 hours after announcing Minnesota Gov. Tim Walz as her running mate, and as the Democratic ticket swung across the country, it drew large, raucous crowds.

After three weeks of unbelievable momentum, Harris now faces the huge — and historically unusual — challenge of sustaining the energy of a fresh campaign for a 90-day...