This was a good item from John Fund the other day:

Republicans won a pair of special elections on Tuesday in Tennessee and Oklahoma, picking up seats held by Democrats for decades. Combined with this month’s capture of the Albuquerque mayor’s office by a Republican for the first time in 28 years, Democrats have reason to be nervous about the approaching November 3 off-year elections. Given their lackluster performance in these races, they could face serious turnout problems that will boost GOP performance.
In Tennessee, Republican businessman Pat Marsh won 56% of the vote to defeat Democrat Ty Cobb. It wasn’t as if Mr. Cobb had a name unknown to voters. His brother Curt had held the seat before resigning to take another government office (and it probably didn’t hurt having the same name as a baseball legend). But Mr. Cobb attributed his defeat to the fact that “a lot of people based their opinions on national issues . . . the health care issue was the main one.”