Attorney Abbe Lowell accused Young of taking much of the money from donor Rachel Mellon for himself instead of using all of it for Rielle Hunter, the former campaign videographer whose affair with Edwards Young was supposed to cover up.
Lowell asked Young whether he used Edwards' affair "for your own means," asking, "Isn't it true that you made up that Rielle Hunter was threatening to go public?" He then demanded, "You didn't ask him for hush money?"
Young said Hunter would threaten to go public when she was upset. He conceded he asked Mellon for extra money while Hunter was living with his family in Florida and then California, The New York Times reported.
During Wednesday's testimony, Lowell called Young a liar.
During questioning by federal prosecutors, Young, who wrote a book chronicling Edwards' 2008 presidential campaign and affair with Hunter, was easily able to recall events and conversations in great detail, but stumbled with the defense. He often answered questions with "I don't know" or "if you say so," The (Raleigh, N.C.) News & Observer reported.
Lowell quoted Young's book, transcripts of speeches, copies of campaign schedules and stacks of e-mail and other correspondence in his effort to damage Young's image and credibility, the newspaper said.
Finally, when asked "You really hate him don't you?" by Lowell, Young replied, "I have mixed feelings."
Young previously testified he and his wife received checks from a wealthy campaign donor that were used to cover up Edwards' affair with Hunter.
Edwards is charged with six felony counts of violating campaign finance laws. He faces up to 30 years in prison and $1.5 million in fines if convicted on all charges.