The Clinton and Trump campaigns on Sunday agreed -- at least publicly -- on one issue, that their 2016 presidential contest remains close with 16 days before Election Day, as Clinton goes to a deep, star-studded bench for closing arguments.

“We're not giving up. We know we can win this,” Donald Trump campaign manager Kellyanne Conway told “Fox News Sunday,” though she also acknowledged the majority of polls showing Democratic rival Hillary Clinton leading.

"We are behind," Conway said on NBC’s “Meet the Press,” at about the same time an ABC News tracking poll showed Clinton leading by 12 percentage points.

The Clinton campaign insisted Sunday that the race remains very close and that it has not shifted focus to competing in traditionally Republican-leaning states to rout Trump and help fellow Democrats win the Senate.

“Secretary Clinton at the beginning of the campaign said she wanted to help all Democrats, up and down the ballot,” Clinton campaign manager Robby Mook told “Fox News Sunday.” “This is not over yet. Battleground states are called battleground states for a reason.”

Still, Clinton stumped hard the previous day in battleground Pennsylvania for the Democratic challenger in the state’s U.S Senate race and amid early indications that registered Democrats are outnumbering registered Republicans in early voting.

And on Sunday, Clinton was in North Carolina, touting fellow Democrat Deborah Ross, who is in a tight race with the incumbent Republican Sen. Richard Burr.

“Unlike her opponent, Deborah has never been afraid to stand up to Donald Trump," Clinton said at a rally in Raleigh.

The former secretary of state will get help on the campaign trail this week from President Obama, who is also trying to help fellow Democrats retake control of the Senate.

They need to win five seats from Republicans in roughly 10 competitive races.

Obama will hold a rally Sunday in tightly contested Nevada before headlining party fundraisers in California.

Obama's recent itinerary has focused on competitive White House states that also have close Senate races. In Nevada, the president is trying to help his party retain the seat of the chamber’s top Democrat, Sen. Harry Reid, who is retiring.

The president is scheduled to speak at a rally in the Las Vegas area for Clinton and Senate candidate Catherine Cortez Masto, a former state attorney general whose opponent is GOP Rep. Joe Heck.

He’ll then travels to San Diego to speak at an event for the Democratic Congressional Campaign Committee, which leads the party’s efforts to elect and reelect Democrats to the House.

Polls indicate that the presidential and Senate races in Nevada are extremely tight. Reid's seat is considered the only one Republicans could reasonably flip to their side this election.

First lady Michelle Obama will join Clinton later this week on the campaign trail -- at a rally Thursday in battleground North Carolina.

Clinton press secretary Brian Fallon, in announcing the first lady and Clinton’s first joint campaign appearance, called Obama an "absolute rock star" on the trail.

Democratic vice-presidential nominee Virginia Gov. Tim Kaine, like Mook, said Sunday that the campaign is “taking nothing for granted,” despite good poll and early-voting numbers.

Trump, the Republican presidential nominee, will hold a rally late Sunday in Naples, Florida.

As of Saturday, more than 5.3 million early votes had been cast, far ahead of the pace at this time in 2012.

Balloting is underway in 34 out of 37 early-voting states, both in person and by mail.

More than 46 million people are expected to vote before Election Day -- or as much as 40 percent of all votes cast.

Kaine on Sunday also shrugged off the possibility of being embarrassed by leaked emails, amid WikiLeaks saying on Twitter that the group has a "surprise" in store for him.

The group, which has been posting stolen emails from Clinton campaign manager John Podesta, posted the Kaine taunts on Thursday and again on Sunday.

Kaine has questioned the authenticity of WikiLeaks' releases and said the emails were hacked as part of an effort by the Russian government to influence the presidential campaign.

On Sunday, he also raised concerns about an AT&T-Time Warner merger, like Trump did on Saturday.

“I share those concerns and questions,” Kaine said on NBC’s “Meet the Press.”

He also said that “pro-competition and less concentration” are “generally helpful,” but that details about the estimated $85 billion deal are still emerging.

Conway also told “Fox News Sunday” that the campaign is “just starting to increase some of our investments on the air,” despite Clinton leading in several battleground states.

Conway argued each are within several points and that Clinton has failed to cross the key 50-percent threshold in any of them while outspending the Trump campaign by millions.

Clinton -- who has been the frontrunner for the entire race against Trump, the unpredictable first-time candidate -- leads in such battlegrounds states as Florida, Nevada, New Hampshire, Pennsylvania and Virginia. Trump leads in Georgia Iowa, Missouri and Ohio.

The Associated Press contributed to this report.