 Donald Trump's running mate will headline the third night of the Republican convention as the Ohio senator is expected to speak. U.S. House Speaker Mike Johnson says Vance is a great choice and has a lot of things going for him. You know, he comes from humble beginnings. He has a great military background. He's a successful author. He's regarded as one of the most thoughtful senators in Congress. Vice President Kamala Harris says Vance will only be loyal to Trump and not the country. Louisiana Radio Network.