 The Republican Convention in Milwaukee. ABC News national correspondent Stephen Portnoy is there. News of Donald Trump's choice of J.D. Vance energized the convention floor. Tracy Sanchez is a delegate from Ohio. Come from grassroots all the way up. I mean, he gets where all of us people, middle class, low class, it doesn't matter. He's a man to understand. At age 39, the first term senator would be the youngest vice president since Richard Nixon was elected in 1952. Protests outside the Republican Convention on Mr. Trump.