WASHINGTON - Donald Rumsfeld is likely to remain at the Pentagon until the spring, enabling him to to stay in the administration through the Iraqi elections and advance his plans for transforming the American military, despite strong pressure from key White House political advisers for him to leave sooner. According to well-placed Pentagon sources, Vice President Cheney has argued the case for Mr. Rumsfeld to remain as defense secretary until at least the spring, and Mr. Cheney would prefer that Mr. Rumsfeld stayed longer. Karl Rove and other White House advisers, however, have maintained that Mr. Rumsfeld has become a...