As he barnstorms the country trying to help Republican allies, President Trump has offered voters this fall a litany of misleading statements and falsehoods that exaggerate even legitimate accomplishments and distort opponents’ views beyond the typical bounds of political spin.

In the past couple of weeks alone, the president has spoken of riots that have not happened, claimed deals that have not been reached, cited jobs that have not been created and spun dark conspiracies that have no apparent basis in reality. He has pulled figures seemingly out of thin air, rewritten history and contradicted his own past comments.

The catalog of inaccurate claims ranges from the weighty to the head-scratching.

He has asserted that construction has begun on his border wall (it has not), that he is one of the most popular American presidents in history (he is not), that he “always” opposed the Iraq war (he did not), that the stock market reopened the day after the terrorist attacks of Sept. 11, 2001 (it did not), that his tax cut was the largest in history (it was not) and that the United States is the only country that guarantees citizenship to those born here (it is not).

As he embarks on a final eight-state, 11-rally blitz before Tuesday’s midterm elections, Mr. Trump has hammered Democrats — not just for their actual policy positions but for some they have not taken. He accused them, without proof, of helping to orchestrate a caravan of Central American migrants; complained that Democrats had opposed opioid legislation when in fact they universally voted for it; and asserted that they would not protect patients with pre-existing conditions — even though that was the heart of President Barack Obama’s health care program.