London — When Keir Starmer was elected to lead Britain's Labour Party in 2020, right after the party suffered its worst general election defeat in 85 years, he made it his mission to make the party "electable." Four years later, and after 14 years of governments led by the rival Conservative Party, Starmer is poised to take Britain's top job. Exit polls from Thursday's parliamentary elections show it's not really about whether Labour will win enough seats for Starmer to become the prime minister and form the next government, but by how wide a margin. The 61-year-old has faced years...