Transcript for Bernie Sanders, Hillary Clinton Staffers Hurl Accusations Before Debate
We start with the charges and countercharges flying as we head into the big presidential debate held on ABC. A federal complaint was filed and overnight there were new developments in the three-way battle between Hillary Clinton, her chief rival Bernie sanders as well as the democratic national committee, the dnc. This all stems from the revelation that members of the sanders' campaign accessed confidential Clinton voter files so how will this drama play out on the debate stage tonight? ABC's Cecilia Vega is right there this morning. Cecilia, good morning to you. Reporter: Hey, Dan, good morning to you. Hours before the debate and two of the three candidates who will be standing at these podiums right behind me are hurling accusations of theft and sabotage at each other. This morning, Hillary Clinton's campaign firing backlashing out at rival Bernie sanders' team for tapping into their private voter files. This was a very egregious breach and our data was stolen. This was not an inadvertent glimpse into our data. Reporter: Clinton's campaign manager even accusing their rival of theft. This breach is totally unacceptable and may have been a violation of the law. Reporter: The punishment for team sanders swift. The democratic national committee cutting off the sanders' campaign's access to its massive database. How people might vote, whether they will vote at all. Which voters they want to win over. But on Wednesday, a software glitch allowed up to four sanders staffers to access Clinton's confidential files. For 40 minutes they searched through them 25 times using phrases like turnout and primary priority looking up Clinton's information on crucial states like Iowa, New Hampshire and South Carolina. If I thought I was doing it wrong I would have tried to hide it and I didn't. Reporter: Josh was fired. He said he did nothing wrong. I saw that there was data. I saw that it was different than ours. And that was really the extent of what I learned relationship the sanders' campaign filing a lawsuit against the dnc accusing the party of trying to help Clinton by cutting sanders off from those crucial voter lists. Overnight the dnc overturning that decision. This is unacceptable. Individual leaders of the dnc can support Hillary Clinton in any way they want. But they are not going to sabotage our campaign. Reporter: And the head of the dnc firing right back. It's baffling to me they would be hurring accusations at us. Our responsibility, my responsibility is to make sure that the integrity of that voter file is restored and preserved. Reporter: Yeah, accusations are just flying this morning. This is being described as a football team getting ahold of a rival's playbook ahead of the big game. This is really valuable campaign data we are talking about, Dan and Paula. Not something you want your rivals to get ahold of. A lot of fodder, I'm sure, for tonight's debate, as well. Cecilia, overnight the dnc conceded they restored his access to toast files in the database so assume this is now closed, right? Reporter: Hardly. Clinton's team want an audit and they pending the outcome they want action taken against their rivals. Not going away certainly before the big stage. Safe to say. Not over, Cecilia, than you. For more let's bring in ABC news political analyst Matthew dowd. My question, first, does this hurt sanders as we had he had into the debate and do you expect Clinton to try to capitalize? Reporter: Well, I think it's probably a small dent in the van of the anti-establishment van that he has. I think his supporters right now are going to stay with him. He may be able to raise money off this based on the fact he was shut out of it. In the end for both campaigns this is like a kidney tone that they want to pass fairly quickly because it's not helpful to either one to get in this tussle prior to this debate tonight. I would expect Bernie sanders to bring this up at some point in the debate tonight. Thank you for invoking the kidney stone this morning on morning television. We appreciate that. Let me ask you aside from the database story, what does each candidate need to do tonight, especially given Clinton's truly commanding lead in the policy? Reporter: Yeah, she has a huge lead. I think first Hillary Clinton needs to do no harm and go into this debate and basically not make a mistake. With the lead she has she just needs to try to run out the clock in the course of this and begin to speak to jeven election voters. I think she needs to start turning her campaign towards independent voters. I think Bernie sanders needs to actually find some ways to draw some really sharp contrasts with Hillary Clinton. He needs a way to get back in the game especially in Ohio and I think martin O'Malley at this point who is far down in the polls needs to figure out ways to preserve his political legacy, to end this campaign in a way that's positive and I think that would be his main goal in the debate tonight. Let's not forget there is a third person on the stage tonight. Before we let you go I'll ask about the republicans. New fox poll shows Donald Trump with a giant lead nationally, 39%. Is this surge driven in part by his controversial plan to ban muslims from entering the country? Well, it seems to institute no. No matter what he says he's been growing in support and growing since August. A majority of republican voters actually support his proposal to ban all muslims is what you're seeing and what he's becoming is no longer the outside of the gop, he is becoming the mainstream of the gop. His positions now represent the mainstream part of the gop and that's what I think the establishment is struggling with. They are struggling indeed. Matt dowd, thank you very much. We'll get much more as the day proceeds. That's why we call him testify none trump.
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