President Bush is about to announce his choice to be U.S. trade representative. An administration official says it will be Congressman Rob Portman. If confirmed by the Senate, the Ohio Republican would replace Robert Zoellick, who has become Condoleezza Rice's top deputy at the State Department. Portman has been one of Bush's chief links to Congress on trade, tax and other issues. He has been a strong advocate of free trade on Capitol Hill, even though he comes from a state that has been hit hard by job losses.