Trump also faulted Tester for voting against his first Supreme Court nominee, Neil Gorsuch, as he prepares to name a second person to the high court.
Trump has meticulously avoided speaking about the movement due to the array of accusations of sexual misconduct brought against him by multiple women as well as dismissing similar claims against men who have worked for him, including his former staff secretary, Rob Porter, who allegedly physically assaulted his two ex-wives.
Sen. Elizabeth Warren (D-MA) took to Twitter to respond to President Donald Trump mocking her claims of having a native American heritage at the campaign rally in Great Falls, Montana. He has also dismissed the special counsel's investigation into potential Russian collusion with Trump's campaign as a "witch hunt" meant to delegitimize his presidency.
He also mentioned he would be meeting with President Vladimir Putin soon, and that getting along with China and Russian Federation is "a good thing".
Trump's eldest son, Donald Trump Jr., received deafening applause as he opened his father's rally, quickly going on the attack against Tester and welcoming Montana Republicans Sen.
The president also said the IQ of Democratic Rep. Maxine Waters of California, with whom he has clashed many times, is "somewhere in the mid-60s". Mr. Trump said Kennedy had made a decision to leave the High Court because he knew the president would pick a stellar replacement.
Tester is one of 10 Senate Democrats running for re-election in states that Trump won in the 2016 election.
It's the president's first trip to Montana, but with Tester a top GOP target this fall, Trump is certain to return and use his popularity to help send Rosendale to replace Tester in the Capitol.
The National Republican Senatorial Committee in a statement called Tester's ads a "pitiful" effort to paint himself as a Trump ally before the rally. "You deserve a senator who actually votes like he's from Montana".
Mr. Trump also took time to attack his Democratic rival for the presidency in 2016, Hillary Clinton, who he said gets "special treatment under the Justice Department".
The U.S. president was in Great Falls, Mon. when he went off on an odd tangent about the size fo the crowds he draws to his speeches.
"Tester said things about him that were terrible and they weren't true", Trump said.
President Trump is scheduled to speak at 4 p.m. Mechanic Shane Hegle said he drove 120 miles (195 kilometers) from his Cut Bank Home to be among the first in line. He says they have to vote Republican in November if they want to protect their families and communities.
Hegle said he voted for Tester in past elections but was undecided now.
The Californian Congresswoman is campaigning for Trump's impeachment. He is expected to travel throughout the summer. Rosendale said he'll back Trump's agenda, while Tester said he'll support the president when it's in the state's interests and oppose him when it's not.