ROUGH CUT (NO REPORTER NARRATION).br br STORY: The top Republican in the Senate, Mitch McConnell, has cast his vote in Kentucky. McConnell is seeking re-election to a sixth term against Kentucky's Secretary of State Alison Lundergan Grimes.br br Polls show McConnell has a slight edge over Grimes. If McConnell hangs on for re-election, and Republicans win control of the Senate he would replace Democrat Harry Reid as Senate majority leader.