Sen. Barack Obama was asked about William "Bill" Ayers in the ABC News Democratic Debate Thursday night, prompting yet another controversy about Obama's relationships with people.

Moderator George Stephanopoulos asked Obama about his relationship with Ayers, who was a member of the Weather Movement in the 1970s. The Weather Movement was responsible for the bombings of the White House, Capitol and other Washington buildings.

From 1999-2002, Obama served on The Woods Fund of Chicago with Ayers. In addition, Ayers gave $200 to Obama's re-election fund in 2002.

"This is a guy who lives in my neighborhood," said Obama. "[He's a guy] who's a professor of English in Chicago who I know and who I have not received some official endorsement from. He's not somebody who I exchange ideas from on a regular basis."

"The notion that somehow as a consequence of me knowing somebody who engaged in detestable acts 40 years ago, when I was 8 years old, somehow reflects on me and my values doesn't make much sense, George," continued Obama.

Obama has received negative attention for his relationships in the past, mainly Rev. Jeremiah A. Wright, who was the pastor of the church Obama frequented.

On Tuesday, Stephanopoulos was a guest on Fox News' Hannity & Colmes show. Host Sean Hannity suggested that Stephanopoulos bring up that Ayers and Obama knew each other during the debate. Stephanopoulos replied, " Well, I’m taking notes now, Sean."

Stephanopoulos denied that he received tips from the conservative political commentator.

The debate, which was held in Philadelphia, Pennsylvania, was the 21st matchup between the two Democratic contenders, Obama and New York Sen. Hillary Clinton.

According to ABC News officials, it was the most watched debate of this campaign cycle, with 10.7 million viewers. The previous record, also held by ABC News, was 9.3 million viewers of the Jan. 5 debate between Democrats in New Hampshire.