With the primary coming on May 20, filing for Kentucky federal races closed on Tuesday, as eight Democrats lined up for the right to take on Senate Minority Leader Mitch McConnell. Several potential top-tier challengers, including Congressman Ben Chandler, state Auditor Crit Luallen and former Attorney General Greg Stumbo all passed on the race, though McConnell does not have a free ride.

Attorney and Iraq war veteran Andrew Horne, a top DCCC recruit in 2006 who nonetheless lost his primary to now-Rep. John Yarmuth, announced his candidacy weeks ago. Still, it may be the second time Horne can't make it through a primary. Wealthy businessmen Greg Fischer and Bruce Lunsford are also in the race, and both are willing to spend money to get their campaigns off the ground.

Fischer is a first-time candidate, while Lunsford ran for governor in 2003 and 2007, losing in both primaries. This time around, he's been encouraged to run by DSCC chair Chuck Schumer, Senate Majority Leader Harry Reid and even new Governor Steve Beshear, who called Lunsford in December, the Lexington Herald-Leader wrote.

All three top candidates face a steep uphill climb. A poll this month, conducted for McConnell's campaign, showed the incumbent 15 points ahead of Lunsford, 22 points up on Fischer and 23 ahead of Horne. Through the end of the 3rd quarter, McConnell had more than $6.8 million in the bank, an almost insurmountable hurdle for any challenger.