Kamala Harris invigorates Democrats in swing state Pennsylvania

In the U.S. state of Pennsylvania, the Democratic Party's switch to Kamala Harris as its presumptive nominee for president has re-energized its campaign for the White House in a key battleground state, grassroots party activists say.

"I believe we're going to have a blue landslide," said Bill Leiner, a volunteer with the Democratic presidential campaign in Allentown, a city of about 125,000 residents.

"People are energized," he added.

In an unprecedented development in modern US electoral history...