A capacity crowd at the Knapp Center at Drake University in Des Moines met President Donald Trump late Thursday, and in a preview of the looming 2020 general election, he hit out at his potential Democratic rivals — referring to them by now-familiar nicknames.

The president referred to Sen. Elizabeth Warren as “Pocahontas,” Sen. Bernie Sanders as “Crazy Bernie” and former Vice President Joe Biden as “Sleepy Joe,” and spoke confidently of victory in November.

“The Democrats will lose because America will never be a socialist country,” Trump said.

Speaking earlier Thursday in Waukee, Iowa, Biden delivered a pre-rebuttal to Trump’s Des Moines rally.

“Welcome to Donald Trump’s world,” Biden said, according to prepared remarks shared by his campaign. “Up is down. Lies are the truth. Allies are enemies. Everything is through the looking glass.”

The former vice president said he had already gone one round with Trump on health care, according to prepared remarks.

“In 2018, I went to 24 states for 65 candidates,” Biden said, according to prepared remarks. “I took on Trump all over the country — and beat him. In fact, we beat him like a drum — and in the process took back the majority in the House. We should remember that this year.”

Iowa House Speaker Pat Grassley spoke just after 5 p.m. — nearly two hours ahead of when the president was scheduled to speak — to urge people to support the president’s reelection.

Grassley criticized Iowa Democratic caucus frontrunner Bernie Sanders for taking a “honeymoon in the Soviet Union.”

Vice President Mike Pence, who introduced Trump, also hit out at Sanders, who Pence said did not approve of the assassination of Qasem Soleimani, an Iranian general killed in a U.S. airstrike on Jan. 3.

“Soleimani was not some ‘government official,’ he was a terrorist and President Donald Trump was right to take him down,” Pence said.

Following the assassination, Sanders issued a statement.

“Trump’s dangerous escalation brings us closer to another disastrous war in the Middle East that could cost countless lives and trillions more dollars,” Sanders said in part of the statement.

Gov. Kim Reynolds also briefly joined Trump on the stage.

“On Feb. 3 we’re gonna caucus, on Nov. 3 we’re gonna vote and on Nov. 4 we’re gonna celebrate four more years,” Reynolds said to cheers and chants of “four more years” from the audience.

Some of the thousands of people in the Knapp Center were there to see Trump though, rather than other Republican officials.

John Lehman, from Grimes, Iowa, said he has never seen a president before.

“I’m 59 years old, you got to try to see one of your presidents sometime,” Lehman said.

Lehman said he supports Trump because he’s “outside the box.”

“[Trump] isn’t politically correct all the time, but what he says a lot of us agree with,” Lehman said. “I just wish he’d say it a little differently.”

Lehman said he would advise Trump to “take the high road.”

“You don’t need to call people personal names, just state your policy,” Lehman said. “I used to coach little league for a long time and I always taught everybody you win with dignity and you lose with grace. That’s how you do it.”

Jim La Velle, a retired electrician from “out by Fort Dodge,” said he is a “life-long hard-nosed conservative” and supports Trump because the president says what he’s going to do and “follows through on it.”

“Most politicians tell you what you want to hear, what you want to know or what you think you want him to do and the candidate will promise all kinds of things,” La Velle said. “They get into office and then they don’t follow through a lot of the times.”

La Velle said Republicans are the ones who are looking out for everyone, citing impeachment as a recent event in government illustrative of Democratic overreach.

“I think it’s really totally made-up,” La Velle said. “Everything that they’re accusing the president of — the Democrats are mainly guilty of, if you really want to know the truth, and the news media stays right behind them and backs them up.”

Some of the rally attendees began to file out of the arena as Trump continued speaking. The president’s address stretched on for more than an hour. The Republican incumbent urged Democrats and Independents to join the Republican Party, calling it a “big tent.” He ended with an appeal to Iowans to vote for him.

“We are going to keep on working, we are going to keep on fighting and we are going to keep on winning, winning, winning,” Trump said. “[…] Ladies and gentleman of Iowa the best is yet to come.”