E.J. Dionne: Kamala Harris gambled and won

Sen. Kamala Harris of California went all in on every level Thursday night, taking a Democratic presidential contest that has been relatively well-mannered and turning it electric and confrontational. She already had the best performance of the night with a series of fluent and passionate statements before she took on former vice president Joe Biden on racial issues. Having underperformed after a strong start to her campaign, she gambled that pressing her advantage by attacking the front-runner