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John Danforth, one of the biggest names in the Missouri Republican Party, now says he wishes he never mentored Sen. Josh Hawley (R-Mo.).

Danforth served in the Senate from 1976 to 1995, and in an interview Thursday with St. Louis Post-Dispatch columnist Tony Messenger, he said seeing supporters of President Trump break into the Capitol on Wednesday was "awful. It was unimaginable."

The rioters, repeating the false claim that the election had been stolen from Trump, arrived as lawmakers were recording the Electoral College votes. Hawley was the first senator to say he would object to the votes, legitimizing the unfounded conspiracies that the election was rigged. Danforth said Hawley told him constituents had been questioning the results, and "my thought when he said that was, 'Josh, what did you say in response? Did you push back at all?'"

There have long been rumblings that Hawley wants to run for president in the near future, and he needs to have the support of constituents who not only will vote for him, but will also send money to his campaign. That's dangerous, Danforth said. "This guy is doing real harm," he told Messenger. "What he's doing to his party is one thing. What he's doing to the country is much worse."

Hawley isn't the "special talent" he thought he was, Danforth lamented, adding that "supporting Josh and trying so hard to get him elected to the Senate was the worst mistake I ever made in my life. Yesterday was the physical culmination of the long attempt to foment a lack of public confidence in our democratic system. It is very dangerous to America to continue pushing this idea that government doesn't work and that voting was fraudulent."