(CNN) House Democratic leaders told rank-and-file members on a conference call on Monday that FBI Director James Comey's letter sent to Capitol Hill in late October indicating more Clinton emails were under review hurt the party's chances in the effort to retake control of the House of Representatives.

The top House Democrat, Nancy Pelosi, who has been publicly critical of the FBI director, called Comey's letter "out of line" according to one Democrat on the call, but said it did have the benefit of boosting fundraising efforts from some small donors to House candidates.

New York Democratic Rep. Jerry Nadler raised the letter on the call, which was scheduled as a periodic update for members on the state of the race, according to the source, and pressed the leadership to give their assessment of the political impact. Few believed that Democrats could win back the majority because of the small number of competitive districts, but some had renewed hope last month when some polls gave Clinton a double-digit lead

"The fact is we had a momentum going with Hillary's campaign," Pelosi said.

She explained to her colleagues that the FBI's announcement helped Republican voters "come home." As a result, the chances for Democrats to flip the balance in the House was weakened as Trump narrowed in on Clinton.

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