JUDY WOODRUFF: Six days to go, and the candidates are trying toes navigate a presidential election map that's still shifting. That had Donald Trump trying today to nail down one must-win state, while Hillary Clinton tries to deny him another.
DONALD TRUMP (R), Presidential Nominee: My second home, you know that. I'm here all the time.
JUDY WOODRUFF: That was Donald Trump today back in vote-rich Florida, a state he's visited often in recent weeks. Today, in Miami, he sounded newly confident.
DONALD TRUMP: And the polls have just come up. We're way up in Florida. I shouldn't say that, because I want you to go vote.
DONALD TRUMP: We are going to pretend we're down. We're down. Pretend, right? We will pretend we're down. No, we got to win, we got to win big.
JUDY WOODRUFF: The race in Florida is, in fact, neck-and-neck, and Hillary Clinton started off her day less than an hour's drive away, visiting an early polling site in Fort Lauderdale.
Clinton, afterward, flew west to campaign in Nevada. And, tonight, she's in Arizona, in past years a Republican stronghold. Her running mate, Tim Kaine, and his wife, Anne Holton, are on the hustings, too, of course, as are President Obama and Vice President Biden, former President Bill Clinton and daughter Chelsea, plus Senators Bernie Sanders and Elizabeth Warren. They're fanning out to election battlegrounds from Ohio to Nevada.
PRESIDENT BARACK OBAMA: If Hillary wins North Carolina, she wins.
JUDY WOODRUFF: The most prominent surrogate of them all spent his time campaigning for Clinton in Chapel Hill, North Carolina.
PRESIDENT BARACK OBAMA: When I said the fate of the republic rests on you, I wasn't joking. Young people here, it's not often that you know your voice will have an impact. Don't let it slip away. Don't give away your power.
JUDY WOODRUFF: Earlier, on the social media platform Now This News, the president called Hillary Clinton's use of a private e-mail server as secretary of state an honest mistake. He also addressed the FBI's review of newly discovered e-mails. He didn't directly criticize director James Comey, but he did say:
PRESIDENT BARACK OBAMA: I do think that there is a norm that, you know, when there are investigations, we don't operate on innuendo, we don't operate on incomplete information, we don't operate on leaks. We operate based on concrete decisions that are made.
JUDY WOODRUFF: Meanwhile, Donald Trump is devoting his whole day to Florida, while his surrogates spread across the electoral map as well, running mate Mike Pence, Trump's children, Donald Jr., Ivanka, Tiffany and Eric with his wife, Lara, former New York Mayor Rudy Giuliani, and former House Speaker Newt Gingrich.
Pence was dispatched to Arizona, ahead of Clinton's visit there tonight, trying to keep the state in the Republican column, where it's been 11 of the last 12 presidential election years.