Kentucky Sen. Jim Bunning (R) announced today he will not seek re-election to a third term. The 77-year-old Hall of Fame pitcher had been considered one of the most vulnerable incumbents this year. Little money and tenuous support from party leaders led to much speculation that he would either retire or face a primary defeat.

Bunning announced his decision in a statement released by his Senate office.

"Unfortunately, running for office is not just about the issues," said Bunning. "To win a general election, a candidate has to be able to raise millions of dollars to get the message out to voters. Over the past year, some of the leaders of the Republican Party in the Senate have done everything in their power to dry up my fundraising. The simple fact is that I have not raised the funds necessary to run an effective campaign for the U.S. Senate. For this reason, I will not be a candidate for re-election in 2010."

Bunning had just $600,000 in campaign funds through the second quarter of this year -- a miniscule amount for a statewide campaign. He spent 10 times that in 2004 and won by just 2 points. Stealing away some of his donors has been Secretary of State Trey Grayson (R), who raised $600,000 through his Senate exploratory committee last quarter -- twice Bunning's total.

Grayson is the party favorite, though whomever the eventual GOP nominee is will face stiff competition in the general election. Attorney General Jack Conway (D) outraised the field in the second quarter with more than $1 million. Also running is Lt. Gov. Daniel Mongiardo (D), who lost the close race to Bunning in 2004.