Hillary Clinton's campaign manager says the Democratic presidential nominee is building a "firewall" in states with early voting.

In a conference call with reporters Friday, Robby Mook touted early vote turnout in North Carolina, Florida and Nevada. He said the campaign is working to "build up a lead that Donald Trump is incapable of overcoming."

Mook said the campaign was targeting voters who were less likely to participate and estimated that at least 40% of registered voters have already cast ballots in those states. He said Trump will have to "outperform Romney on Election Day" to pull ahead in those states. He was referring to 2012 Republican nominee Mitt Romney.

Mook said Clinton was winning support from the "Hillary Coalition." He said that includes Latinos, Asian-Americans and college-educated women.

Meanwhile, Trump is continuing to hit on the cloud of controversy that hangs over Clinton.

He summed it up to an Atkinson, New Hampshire, audience Friday by saying: "What a mess."

He added:  "And all she had to do is follow the rules."

Trump was referring to controversies surrounding Clinton's use of a private email system while secretary of state and the work of the Clinton family foundation.

Trump again speculated that a Clinton presidency would be marred by investigations and trials, creating "an unprecedented constitutional crisis." The FBI recommended against charging anyone in connection with the email setup this summer.

Trump also accused the Department of Justice of doing everything it can "to protect their angel."

Trump is scheduled to hold a rally in Reno this Saturday afternoon at the Reno-Sparks Convention Center.

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