WASHINGTON – President Donald Trump offered rare insight into his midterm election strategy at a rally in Montana on Saturday, telling an audience there is "no reason to go on" about the nation's economy while a "crisis" is brewing on the border.

"I can only go for four or five minutes with that stuff, and then the crowd says 'we love you,' and then they start dwindling off," Trump told a rally in Belgrade, Montana, the latest stop in his final campaign swing before Tuesday's election. "When we’re fixing a problem or fixed a problem there’s no reason to go on about it for 45 minutes."

Instead, Trump has revived immigration as a major theme at his rallies, relying on a caravan of Central Americans making its way through Mexico as a symbol of what he describes as everything that's wrong with U.S. immigration laws. Democrats counter the president is using the caravan, still hundreds of miles from the border, to instill fear.

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Trump, who regularly does discuss unemployment and job growth at his rallies, was campaigning in Montana for Matt Rosendale, who is running against incumbent Democratic Sen. Jon Tester. Later Saturday he will campaign in Florida before holding on series of rallies on Sunday and Monday.

"But we have a problem at the border," Trump said told the audience. "We have our military now on the border. And I noticed all of that beautiful barbed wire going up today. Barbed wire, used properly, can be a beautiful sight."

Trump then launched into a line he has been employing regularly at his rallies in the closing days of the campaign, tying the immigration issue to female voters who could be a pivotal demographic in an election that will decide control of the House and Senate.

"Women want safe neighborhoods for their families, great schools for their children and they want violent predators like we're talking about to be thrown in jail or thrown the hell out of our country," Trump said.

Trump has provided no evidence the caravan includes "violent predators." He has pointed to estimates from the Department of Homeland Security released this week that "over 270 individuals along the caravan route have criminal histories, including known gang membership." The department has not said what those numbers are based on.

Some Republicans have questioned why the president isn't talking on the stump more about the economy, which has performed well during his first two years in office. Unemployment fell to 3.7 percent last month, a level not achieved since the 1960s.

Polls indicate the economy, immigration and health care are all top issues for voters.