PROVIDENCE -- Margaret B. Crosby is aiming to become the first black Republican woman elected to Congress. Crosby, a scholar who lives in Providence, has announced plans to take on Dave Rogers in a GOP primary, with the winner challenging Democratic U.S. Rep. Patrick J. Kennedy. While African-Americans are now identified more closely with the Democratic Party than the GOP, that was not the case earlier in American history, said Crosby, who has a doctorate in history from Brown University. Crosby said congressional Republicans approved the 13th, 14th, 15th and 19th Amendments to the U.S. Constitution, thereby abolishing slavery, providing...