Very much in re-election mode even before next month’s midterms, President Donald Trump took jabs at potential Democratic candidates at an Iowa rally Tuesday night, calling their party “an angry mob.”

“You don’t hand matches to an arsonists. And you don’t hand power to an angry mob,” he told rallygoers in Council Bluffs, Iowa. “If you want to defeat the swamp, you’ll have to elect Republicans.”

He criticized what he called Democrats’ “outrageous actions” during new Justice Brett Kavanaugh’s confirmation process.

The opposition party, he contended, has shifted so far to the left, they believe “Pocahontas to be a rational person.” That was a reference to his controversial nickname for Sen. Elizabeth Warren, who has claimed Native American ancestry.

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“Oh, I hope she runs, I hope she runs,” he said of the Massachusetts Democrat. “We can finally get down to the fact if she has Indian blood.”

The crowd, many in “Make America Great Again” gear, roared its approval.

Trump then turned his attention to a New Jersey Democratic senator and former mayor: “We won’t talk about Cory Booker who ran Newark into the ground.”

Next up was Connecticut Democratic Sen. Richard Blumenthal, who once indicated he served in combat in the Vietnam War only for it to be discovered that he hadn’t: “We won’t talk about Da Nang Dick. One problem … he was never in Vietnam.”

Trump was in Iowa to stump for two vulnerable House Republicans, Reps. David Young and Rod Blum. Inside Elections with Nathan L. Gonzales rates Blum’s race against Democrat Abby Finkenauer as Leans Democratic and Young’s race against Democrat Cindy Axne as a Toss-up.

After earlier in the day teasing a “big announcement” at the rally, the president announced his administration is ending a summertime ban on a blend of gasoline with higher amounts of ethanol. The move is expected to be a boon for Iowa and other corn-producing states — and a possible shove in the positive direction for the state’s vulnerable GOP incumbents.

“We’re going with E15 year-round,” he said, using industry shorthand for the fuel, noting that he was fulfilling 2016 campaign promise.

The president, as he talked to reporters while leaving the White House earlier in the day, downplayed suggestions that the ethanol decision was politically motivated. He said he wanted to help farmers and that selling more gasoline with ethanol would help air quality.

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Besides the congressmen, Trump also rallied supporters behind GOP Gov. Kim Reynolds, who is in a tight race with Democrat Fred Hubbell, whom several polls give a narrow lead less than a month until Election Day.

Trump called Reynolds onstage, and like other Republican candidates who have taken the mic at rallies, she praised him for keeping his promises: “We’re getting things done.” 

“We’re going to keep Iowa moving,” she added. “Republicans need your support. And to do that, we need to go vote.”

Trump had delivered a similar message, signaling again that Republicans need a big turnout to keep the House.

The president hit Reynolds’ Democratic opponent, accusing him of wanting to open the state’s borders, issue more regulations and raise taxes.

The outcomes of the two Iowa House races could have major consequences for Trump if they help Democrats take back the House next month after eight years of GOP control.

First, it would stall much of his domestic agenda while giving House Democrats more sway over everything from spending bills to immigration legislation to an overhaul of criminal justice policy to the sweeping infrastructure bill the White House wants to pursue with a new Congress.

But the stakes are even higher for Trump. That’s because rank-and-file House Democrats could force their leadership to begin impeachment proceedings against the president — especially if special counsel Robert S. Mueller III completes his Russia election meddling probe and delivers a report to Congress with damning information about the president.

Trump repeatedly encouraged those in attendance to vote early, another sign of how important turnout will be for the GOP.

He appeared annoyed with his staff as the crowd loudly chanted, “Go big red.” That was a reference to the Nebraska Cornhuskers — Council Bluffs is just over the Missouri River from neighboring Nebraska. Trump said he planned to speak to his staff because he concluded there were more people from Nebraska, and he came to stump for Iowa GOP candidates.

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