Thursday I watched Donald Trump’s most recent campaign rally in Great Falls, Montana. He was there on behalf of Matt Rosendale, who is attempting to defeat incumbent Democrat Sen. Jon Tester. Trump won Montana by 20 points in 2016, down from George Bush’s 25-point win in 2000, indicative of the changing political landscape in the Big Sky state over the last 20 years. That change is primarily due to an influx of wealthy liberals like bison “dude rancher” Ted Turner, who have displaced native Montanans in order to “preserve” their vast landholdings.

My primary interest in catching this rally was to take the temperature of Trump’s grassroots support, and to hear his latest remarks, which outline the Republicans’ 2018 campaign strategy. Overall, his remarks were predictable crowd pleasers, and he did an outstanding job staying on message regarding his criticism of Turner’s water boy Tester. “You deserve a senator who doesn’t just talk like he’s from Montana,” declared Trump. “You deserve a senator who actually votes like he’s from Montana.”

He brought down the house with his offer to 2020 Demo presidential prospect Elizabeth Warren: “She’s based her life on being a ‘minority.’ … I’m going to get one of those little DNA kits and if I’m debating her, we will toss it to her and say, ‘Pocahontas, I’ll give you a million dollars to your favorite charity if you take the test to show you’re an Indian!’”

But there was one serious gaffe that departed from his otherwise well-received populist message, though his grassroots base has adjusted to his now-epic errant Trumpisms.

In Trump’s brash New York style, comparing his popularity to that of Ronald Reagan, he stated: “I just left Wisconsin. … Think of Wisconsin. Reagan had his great win. He won every state except one, the great state of Wisconsin. I won Wisconsin, first time since Dwight Eisenhower in 1952. … We had a great victory, but think of it. Not since Dwight Eisenhower in 1952.”

Now, Trump was not elected because of his mastery of U.S. history, but those who composed his tele-prompted remarks should have caught this error. It is offensive to those of us who were deeply engaged on the frontlines of the Reagan Revolution. Clearly his writers, and thus Trump, were confusing Wisconsin with Minnesota, the one state President Reagan lost in his landslide 49-state 2004 victory over Walter Mondale, who was from Minnesota. Reagan won Wisconsin both in 1980 and 1984.

That notwithstanding, one such gaffe is permissible. But twice, not so much.

Last Thursday in Mount Pleasant, Wisconsin, Trump made the same errant claim: “Wisconsin hadn’t been won by a Republican since Dwight D. Eisenhower, in 1952. And I won Wisconsin. And I like Wisconsin a lot, but we won Wisconsin. And Ronald Reagan, remember, Wisconsin was the state that Ronald Reagan did not win.”

For the record, after Eisenhower’s Badger State victories in 1952 and 1956, Wisconsin voters supported Republicans in 1960 (Nixon), 1968 (Nixon), 1972 (Nixon), 1980 (Reagan) and 1984 (Reagan), before Trump’s 2016 victory.

As I noted back in 2016, Trump started a Reagan revival, even borrowing Reagan’s campaign slogan, “Let’s Make America Great Again.” He is now well down the road to making America great again.

But before his next campaign stop, my constructive advice to President Trump regarding his Wisconsin claims is this: One of his speech writers needs to hear “You’re Fired,” and Trump needs to spend a little more time getting his facts right before promoting his popularity over that of President Reagan.