Republican presidential nominee Donald Trump. Justin Merriman/Getty Images Donald Trump lashed out at the media on Monday for not reporting that he is "winning" the 2016 race for the White House, just one day after the Republican nominee's campaign manager conceded he was "behind" Hillary Clinton, the Democratic nominee.

"We are winning and the press is refusing to report it," Trump tweeted Monday morning. "Don't let them fool you — get out and vote!"

Kellyanne Conway, the Trump campaign manager, acknowledged Sunday on "Meet the Press" that Clinton was leading in the polls with just over two weeks to go until Election Day.

"We are behind," Conway said. "She has some advantages."

Trump has criticized the press throughout his campaign, but he has intensified his attacks in recent weeks.

Polls show his campaign down nationally and in key battleground states. The Republican nominee trails Clinton by almost 6 percentage points in the RealClearPolitics average of recent national polls, and Business Insider's latest Electoral College projection gives Clinton a 322-to-187 advantage, well over the threshold of 270 electoral votes needed to win the presidency.