Donald Trump. Pool/Getty Images Almost half of registered Republicans believe that President Donald Trump won the popular vote in the 2016 presidential election, even though nearly 2.9 million more Americans voted for Hillary Clinton, his Democratic opponent.

The Politico/Morning Consult poll found that 47% of Republicans and 49% of Trump voters believe the president earned more individual votes than Clinton did. Forty percent of Trump voters said that Clinton won that count.

While 72% of all respondents said Trump won the electoral college, only 59% said Clinton won the popular vote.

Trump has repeatedly promoted the false claim that he won the popular vote, arguing, with no evidence, that millions of illegal votes were cast for Clinton.

In a tweet just days after he won the general election with 304 electoral votes, he wrote that he "won the popular vote if you deduct the millions of people who voted illegally."

In another tweet in December, Trump said he would have campaigned differently, and thus triumphed in the popular vote, if presidential elections were determined by the outcome of the popular vote.

"I would have done even better in the election, if that is possible, if the winner was based on popular vote — but would campaign differently," he said.

During his first meeting with congressional leaders after taking office in January, Trump claimed that between three million and five million undocumented immigrants voted for Clinton, thus handing her an illegitimate popular vote victory.

Earlier this month, the White House formed a controversial voter-fraud commission, chaired by Vice President Mike Pence and Kansas Secretary of State Krish Kobach, which is seeking detailed voter data from state governments. The request has sparked outrage from Democrats and others who say the effort is an attempt to suppress voting rights. More than a dozen states have refused to turn over any of the data and at least 44 have only released some of the information.

Last week, Kobach told MSNBC that the country "may never know" whether Clinton won the popular vote.

Politico/Morning Consult's survey of 3,981 registered voters was conducted between July 20-24 and has a margin of error of plus or minus 2 percentage points.