 ABC News national correspondent Stephen Portnoy reporting from the site of the GOP convention in Milwaukee. While his memoir of his working class upbringing brought him renown, James David Vance is still unknown to most of America. Tonight, here in this hall, J.D. Vance will have something of a national debut as he makes his case for Donald Trump's re-election and for his own ascension to the second highest office in the land. RNC coverage continues live on KRMG at 6 p.m.