Cool, swinging a state from a solid R to a leans R makes taking a Senate seat a lot more likely. I'm not familiar with Democratic leaders in Tennessee, but I'm sure one of them could make a strong campaign
Mark Kirk is not a good example of how a seat can swing from one party to the other, though. Giannoulias, and the Democratic Party in Illinois as a whole, was tainted by working with Blagoviech's administration, given that Blagoviech's impeachment and very questionable appointment of Roland Burris as Obama's replacement. It was as much a referendum on the status of state government as it was electing a senator, and Mark Kirk did a good job of being a centrist candidate who could appeal to voters disillusioned by Blagoviech's blatant corruption. A better example would be Joni Ernst flipping Iowa's 2nd senator red after Tom Harkin's retirement in 2014, since she ran a successful campaign after a long-term senator retired and the Democratic newcomer was unable to capture the respect/interest of former Harkin voters