Clinton Blames Comey for Stopping Campaign Momentum: Source

Former Secretary of State Hillary Clinton greets supporters and members of her staff during a news conference at the New Yorker Hotel on November 9, 2016 in New York City. Getty Images

Hillary Clinton told donors on a conference call Saturday that she blames FBI Director James Comey for stopping her campaign's momentum in the final stretch, a source on the call told NBC News.

“There are lots of reasons why an election like this is not successful," Clinton said on the call, according to the source. "But our analysis is that Comey’s letter raising doubts that were groundless, baseless, proven to be, stopped our momentum,” she said.

President Elect Donald Trump is booed as he walks through the lobby of The New York Times Building after a 75-minute meeting with Times journalists. The lobby of the Times building is open to the public, and a large crowd had gathered by the time he departed. (Published Tuesday, Nov. 22, 2016)

Just weeks before the election, Comey sent a letter to congress that said the FBI found additional emails pertinent to the investigation into Clinton's use of a private server while secretary of state.

The emails were later determined to not warrant further action by the FBI.