Republican Sen. Jim Bunning (search) held off a strong challenge by Democrat Daniel Mongiardo (search) on Tuesday to win a second term, scoring a razor-thin victory following a campaign in which the candidates exchanged increasingly sharp personal attacks.

With all but four precincts reporting, Bunning beat Mongiardo by only about 18,000 votes out of more than 1.7 million cast.

Bunning, 73, a Hall of Fame major-league pitcher, once was viewed as a lock to win re-election, but saw his edge slip away in the campaign's closing days.

He once compared Mongiardo's appearance to one of Saddam Hussein's sons, and claimed his wife wound up "black and blue" after an unsubstantiated encounter with his rival's staffers at a political picnic.

The senator also admitted he was unaware that a group of Army reservists had refused a convoy mission in Iraq, and said he hadn't read a newspaper in weeks and relied on FOX News for information.

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In his only "debate" with Mongiardo, Bunning participated from the Republican National Committee offices in Washington, and his campaign later acknowledged he used a TelePrompTer for some remarks.

On the issues, Mongiardo, a state senator and surgeon, branded Bunning as ineffective and offered several populist-tinged promises to help families strapped by high costs for health care, prescription drugs and college tuition.

Bunning stressed his conservative credentials and alliance with President Bush, counting on a boost from the president's name at the top of the ballot.

Bunning acknowledged Monday that he had not run a perfect campaign.

"The only time I've ever been perfect was for about two hours in 1964," he said in reference to a perfect game he pitched for the Philadelphia Phillies.

The personal attacks reached a flash point in the final week when two Bunning surrogates, both state senators, made comments during a Bunning bus tour that seemed to suggest that Mongiardo is gay. Bunning was present for the remarks and refused to disavow them.

Mongiardo, a 44-year-old bachelor, said he is not gay, and said Bunning had violated two of the Ten Commandments — those against "false witness" and killing. Mongiardo claimed the attacks killed his character.

Bunning accused Mongiardo of spreading untrue rumors that the Republican wasn't mentally fit to keep his job, and the incumbent released letters from two doctors stating he is in excellent health. Mongiardo dismissed Bunning's accusation as "another absurd comment."

On the stump, Mongiardo accused Bunning of being out of touch with average families strapped by rising costs for prescription drugs, gas and college tuition. Mongiardo turned health care into his main theme, arguing the current system is too expensive and inefficient and covers too few.

The challenger proposed offering tax credits to help small businesses provide health insurance to their employees. He called for expanding Medicaid to include families who earn too much to qualify for the federal-state insurance program but too little to afford private insurance.

Bunning stressed his support of tax cuts, the tobacco quota buyout, a Medicare drug benefit and Bush's handling of the war against terrorists. The senator noted his assignment on the Senate Finance Committee, which shapes the nation's tax policy.

Bunning spent 12 years in the U.S. House before his election to the Senate in 1998 by a razor-thin margin over Democrat Scotty Baesler.