 From ABC News, I'm Chuck Severson. Donald Trump chooses a relatively new Ohio senator as his running mate, and both are officially nominated at 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, and he gets what all of us people need.