David Jackson

USA TODAY

WASHINGTON — White House spokesman Sean Spicer said Tuesday that President Trump continues to have concerns that 3 million to 5 million people voted illegally in last year's elections, though observers, including Republican leaders, say there is a total lack of evidence.

"It was a comment that he made on a long-standing belief," Spicer said a day after Trump claimed to members of Congress that people who are in the country illegally caused him to lose the popular vote to Democrat nominee Hillary Clinton by almost 3 million votes.

In his meeting with House members at the White House on Monday, Trump echoed a Twitter post he made in November: "In addition to winning the Electoral College in a landslide, I won the popular vote if you deduct the millions of people who voted illegally."

Clinton took almost 3 million more votes than Trump, but the New York businessman won more states and collected more than than 300 electoral votes, well over the necessary majority.

As candidates, lawmakers, government officials and election observers disputed Trump's claim, congressional Republicans expressed dismay at Trump's return to the topic.

Sen. Lindsey Graham, R-S.C., told NBC News that such unfounded claims can undermine his ability to govern, and perhaps the government itself.

"To continue to suggest that the 2016 election was conducted in a fashion that millions of people voted illegally undermines faith in our democracy," Graham said. "It's not coming from a candidate for office, it's coming from the man who holds the office."

Spicer said Trump made an off-hand comment during a meeting on his legislative agenda.

"He believes what he believes," Spicer said.

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