Recent polling shows that, despite apologies and denials of wrongdoing, the federal probe into Mayor Vincent Gray’s 2010 campaign remains the main obstacle to his re-election.

Yet, when given the chance to outline for voters specifically what happened four years ago, and explain why they should trust him with another four years in office, Gray’s answers were not to the point during a Wednesday night debate.

“I’ve indicated I’ve tried to provide what information I know,” he said when asked if he owed voters not just an apology, but a detailed accounting of what happened in 2010. An ongoing investigation by U.S. Attorney Ronald C. Machen Jr. has resulted in guilty pleas to federal charges from four Gray campaign associates stemming from schemes that allegedly helped Gray win the election.

In a quick pivot Wednesday, Gray steered the live broadcast debate hosted by WAMU 88.5 to his background.

“You know, one of things that I’ve tried to do is help people understand who Vince Gray is in the first place,” he said. “I was born and raised in the District of Columbia. I was raised in a one-bedroom apartment where I grew up sleeping on a rollaway bed next to my brother in the living room.”

The Northeast D.C. native then described his long career in non-profit social services, the work he did on behalf of the city’s homeless population as director of the D.C. Department of Human Services and his six-year tenure on the District Council, before being elected mayor.

Earlier in the debate, Gray was asked to talk about his cooperation with federal prosecutors to help root out the wrongdoers.

“The cooperation that was asked of us has either come through me or has come through my attorney,” Gray said. In January, District Attorney General Irvin B. Nathan agreed to provide Machen with all mayoral documents related to a settlement with alleged shadow campaign financier Jeff Thompson.

“I will assert once again that I did nothing wrong,” Gray continued, adding that he had also offered a campaign finance reform bill to the council.

Machen has stated that his office needs more information. He also indicated attorneys have been trying to talk to people involved.

When pressed, Gray said he has not personally met with Machen. He dodged a follow-up question on whether he had been asked for a meeting.

“My attorney has been the one who has been relating to this issue,” he said.

A majority of Democrats — 53 percent — say they are less likely to vote for Gray in the April 1 primary given the 2010 investigation, according to a NBC4/WAMU/Washington Informer/Marist poll, and 46 percent believe Gray was involved in unethical, but not illegal actions. About a quarter of Democrats believe he was behind something illegal, while 15 percent say he did nothing wrong.

Despite the questions, 56 percent of D.C. residents approve of how Gray is doing in office and he leads the field of eight candidates. According to the poll, 28 percent of Democrats plan to vote for him in April.