On Monday, Akin described Woods as a "whistleblower."
"If Shepard was making business deals in the Senate dining room, that is a clear abuse of power and privilege," Akin said.
McCaskill's campaign has described Woods as a disgruntled former employee who lied to Shepard about his past criminal convictions involving fraud and embezzlement and dismissed his accusations as meritless. Legacki said the conversations described by Woods in the audio recording never occurred.
McCaskill said, "It's October and I'm running for office and two things happen: The leaves change and they unfairly attack my husband."
Reporter David Lieb in Jefferson City, Mo., contributed to this report.
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