WASHINGTON - The presidential race is getting most of the national attention this year, but the battle for the U.S. Senate is just as fierce - and the outcome will have an impact on the fortunes of whoever wins the White House. With the Senate currently in Republican hands by a tiny margin, a shift of just two seats could throw control to the Democrats. Or the election could help Republicans solidify their power - and dethrone the top Democratic leader, Sen. Tom Daschle, D-S.D., one of this election's most endangered incumbents. "It's nip and tuck," said Steven Smith, a...