President Trump held a Tuesday night rally in Council Bluffs, Iowa – the latest stop in the president’s busy tour boosting GOP candidates ahead of next month’s midterm elections.

He began by announcing a decision to remove a federal ban on summer sales of gasoline with high-ethanol blends, thus permitting year-round sales of gasoline with 15 percent ethanol or E15.

“We’re going with E15 year round. I made that promise to you during the campaign. I made that promise to you during the primaries,” he said. “Promises made, promises kept.”

The move is seen as particularly helpful for Iowa and other farm states.

Trump spent the majority of the rally, however, slamming Democrats while urging attendees to vote for Republicans. “The Democrats have become totally unhinged,” he said. “They’ve gone crazy.”

“If you want to drain the swamp, you must defeat the Democrats,” he added. “This election is about security and it’s also about prosperity,” he said, later claiming that “Democrats are the party of crime. Republicans are the party of safety.”

“The only reason to vote Democrat is if you are tired of winning,” Trump said.

While largely focused on criticizing the Democrats, the president also recognized Iowa Sen. Chuck Grassley, the Senate Judiciary Committee chairman who recently helped push through the confirmation of Trump nominee Brett Kavanaugh to the Supreme Court. Grassley, Trump said, is a “very tough cookie.”

Kavanaugh, confirmed Saturday in a 50-48 vote, had his first full day on the bench on Tuesday.

It’s been a “truly historic week for America and you know what I’m talking about,” Trump said, adding that the Democrats tried to ruin Kavanaugh. “They want to destroy everything,” he said. “That’s all their good at. What the Democrats did to Brett and his beautiful family is a national embarrassment and a national disgrace.”

To avoid the Democrats’ “politics of anger and destruction,” the president said, citizens need to vote on Nov. 6.

“Never forget that in 2016 we had the greatest movement in the history of our country,” he said to cheers. “With your vote you can do so much.”

The Associated Press contributed to this report.