Senate Minority Leader Mitch McConnell of Kentucky, accompanied by Sen. John Barrasso (R-Wyo.), speaks to reporters on Capitol Hill in Washington on March 5. The South, where President Barack Obama and his party have struggled for years, will be Democrats' toughest battleground in the 2014 fight for control of the Senate. A trio of incumbents must face the consequences of having voted for Obama's signature health care law, but first Republicans must settle primaries in several states, including a challenge to McConnell. <br>The Associated Press