So the people who track such things say this presidential race is a dead heat. Well some of this year's Senate races are, too. In South Carolina, Democrat Inez Tenenbaum and Republican Congressman Jim DeMint meet tomorrow in the fifth of six debates. The candidate who wins the seat of retiring Democrat Senator Ernest Hollings could help decide which party controls the Senate. Commentator Zanny Minton Beddoes says voters may have to choose between protecting their pocketbooks and their local industries.