WASHINGTON (CN) - President Donald Trump took to Twitter on Wednesday to call for an investigation into voter fraud, doubling down on his unsubstantiated claims that illegal voters robbed him of a victory in the popular vote.
Trump has provided no evidence to back up his claims that millions of people voted illegally and has continued making them even after entering the White House last week.
Trump lost the popular vote to Hillary Clinton by nearly 3 million votes, but was nevertheless able to secure enough votes in the electoral college to win the presidency.
Speaking at a press briefing on Wednesday, White House Press Secretary Sean Spicer backed Trump's allegations, suggesting the inquiry Trump tweeted about could look at states like California and New York that were not subject to recounts after the November election.
"The isn't just about the  election, this is about the integrity of our voting system," Spicer said.
Trump's continued insistence that widespread voter fraud occurred has drawn ire and taunts from lawmakers, Democrats and Republicans alike. They say Trump's comments are dangerous and undermine core democratic principles.
"The president's dangerous falsehoods must stop," Sen. Patrick Leahy, D-Vt., said in a statement. "I hope that congressional Republicans can explain to President Trump that he should be reaching out to all Americans rather than furthering the divisive campaign rhetoric he used on the trail."
Sen. Lindsey Graham, R-S.C., who briefly challenged Trump for the Republican nomination, also called on Trump to stop throwing around such explosive allegations without backing them up in any way.
"To continue to suggest that the 2016 election was conducted in a fashion that millions of people voted illegally undermines faith in our democracy, it's not coming from a candidate for the office, it's coming for the man who holds the office," Graham told reporters Tuesday. "So I am begging the president, share with us the information you have about this or please stop saying it."
The claims, which Trump began to repeat shortly before the election to support his theory the election was "rigged" against him, were revived when Trump repeated them to Congressional leaders in a meeting on Monday.
When asked about Trump's claims at a news conference Tuesday, Senate Majority Leader Mitch McConnell refused to directly refute them, instead saying voter fraud "does occur" and acknowledging both parties disagree on the extent.
Senate Minority Leader Chuck Schumer later accused Republicans of not standing up against Trump's unfounded claims, calling on Trump to stop repeating the charges for the sake of the country.
"The bottom line is simple: you cannot run a government, you cannot help people, you cannot keep America safe, if you don't actually admit to the facts, plain and simple," Schumer said told reporters. "And unless that starts happening, this country is going to have real trouble."
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