(CNN) President Donald Trump arrived in western Pennsylvania on Saturday night with a message for the Republican running there: Don't embarrass me.

Trump rallied outside Pittsburgh for state Rep. Rick Saccone ahead of Tuesday's special congressional election for a seat in the heart of America's steel industry, where Trump beat Hillary Clinton by 20 percentage points in 2016.

But after immediately endorsing Saccone when he hit the stage, Trump pivoted to a 75-minute torrent of policy musings, political attacks and presidential campaign previews.

He opened his whirlwind speech by touting his administration's new tariffs -- 25% on steel imports and 10% on aluminum imports -- before wading into the issues surrounding North Korea, previewing his 2020 campaign slogan, discussing the merits of giving drug dealers the death penalty and attacking a series of familiar targets.

He called NBC host Chuck Todd -- who he's nicknamed "sleepy eyes" -- a "sleeping son of a bitch" and described Democratic Rep. Maxine Waters as a "very low IQ individual."

At one point, he mocked the idea of being "presidential."

"If I came like a stiff, you guys wouldn't come here tonight," he said.

Trump delivered "about five minutes" of what had been scripted for Saturday night's rally, a White House official familiar with the speech said. He had discussed his message on North Korea with aides shortly before taking the stage. But he scrapped his prepared remarks on Saccone, improvising and at one point handing the microphone to Saccone, too.

When his attention was on the race here, he seemed keenly aware of the size of his own victory in the district in 2016.

"This guy should win easily," Trump said.

He added at another point: "I hate to put pressure on you, Rick."

Polls in Pennsylvania's 18th District show a tight race. A loss by Saccone to Democratic Marine veteran and former prosecutor Conor Lamb would be seen as a major warning sign for the GOP ahead of November's midterm elections.

Trump and the Republican Party have gone all in to prevent an embarrassing defeat. Trump endorsed Saccone in January, and outside Republican groups have spent more than $10 million on the race in support of Saccone, who's weak fundraising numbers have seen him outraised by Lamb by nearly five-to-one in the first seven weeks of the year.

"The whole world, remember that. They're all watching," Trump told the crowd in Moon Township. "This is a very important race. Very important."

Trump referred to the Democrat as "Lamb the sham" and said he'd vote with his party in Washington if he's elected. Republicans have tried to tie Lamb to Democratic leader Nancy Pelosi, but Lamb has said he does not support Pelosi.

"He's going to vote the party line. He doesn't care about us," Trump said. "But for getting your votes, he's talking about how much he likes tariffs, which is my baby."

Trump said he heard the 33-year-old Lamb was "nice-looking" but said, "I think I'm better-looking than him. I do. I do. I do. And he's slightly younger than me."

"He's OK. He's all right," Trump said of Lamb. "Personally, I like Rick Saccone. I think he's handsome."

Death penalty for drug dealers

Trump praised other countries for imposing the death penalty or life in prison for drug dealers, saying the United States should consider similar penalties.

"I think it's a discussion we have to start thinking about. I don't know if we're ready -- I don't know if this country's ready for it," Trump said.

He said those convicted of killing just one person in shootings and stabbings at times face the death penalty or life in prison without parole. But, he said, someone can "kill 5,000 people with drugs because you're smuggling them in and you're making a lot of money and people are dying," and go without serious punishment.

"That's why we have a problem, folks. I don't think we should play games," Trump said. "Now, I never did polling on that -- I don't know if that's popular, I don't know if that's unpopular. ... But these people are killing our kids and they're killing our families, and we have to do something. We can't just keep setting up blue-ribbon committees with your wife and your wife and your husband, and they meet and they have a meal and they talk, talk talk talk, two hours later, then they write a report."

Trump's 2020 slogan

At the campaign rally, Trump also offered a preview of his own 2020 re-election race, telling the crowd he's decided on a replacement for his "Make America Great Again" slogan.

"Our new slogan, when we start running, in -- can you believe it, two years from now -- is going to be, Keep America Great, exclamation point," Trump said.

He lambasted Vermont Sen. Bernie Sanders and Massachusetts Sen. Elizabeth Warren -- who he again called "Pocahontas" -- while predicting that media would become bored covering their anticipated 2020 campaigns.

He said the candidate he most wants to run against in 2020 is Oprah Winfrey, predicting the campaign "would be a painful experience for her."

"Oh I'd love Oprah to win, I'd love to beat Oprah. I know her weakness," he said.

Claiming credit for the Olympics

Trump also touted his role in South Korea's hosting of the Winter Olympics, claiming credit for temporarily reducing the nuclear threat posed by North Korea.

"It's little hard to sell tickets when you think you're going to be nuked," he said.

His comments come days after the White House confirmed Trump will meet face-to-face with North Korean leader Kim Jong Un.

"Who knows what's going to happen? It could happen, it doesn't happen," Trump said of the meeting. "I may leave fast, or we may sit down and make the greatest deal for the world and for all of these countries, including, frankly, North Korea, and that's what I hope happens."