Aiming to boost vulnerable Nevada Sen. Dean Heller on his home turf amid a fierce re-election bid, President Donald Trump dubbed the Republican a “champion” of conservative causes and called his Democratic foe “wacky.”

“There’s been no better friend — we started off slow — but I’ve had no better friend in Congress than Dean Heller,” Trump said Thursday at a campaign rally in Las Vegas.

Trump first singled out Danny Tarkanian, who is in a close fight for Nevada’s open 3rd District seat. Trump then soon hailed Heller as a “friend,” saying during his first months in office “he didn’t like me, I didn’t like him.”

Heller’s appearance at the rally was meant to give him a boost in what is shaping up to be a highly competitive Senate race against Democratic Rep. Jacky Rosen. That contest, along with Tarkanian’s House bid and the race in the open 4th District, make the Silver State key to deciding control of the House and Senate come January.

As he has when talking about other GOP candidates, Trump warned the crowd that a vote for Rosen would be a threat to Second Amendment rights. He also branded the freshman congresswoman with one of his signature nicknames: “Wacky Jacky.”

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“She’s wacky,” he said as the crowd laughed in unison, later telling them that Rosen “is never going to vote for us” and saying she would not help put Judge Brett Kavanaugh on the Supreme Court should his confirmation slide beyond Election Day. And he claimed Rosen was “bought and paid for” by her “out-of-state donors,” whom he alleged are funding “90 percent of her campaign.” He dinged her votes against the GOP tax overhaul and health care legislation, painting her as pro-high taxes and a proponent of the 2010 health care law.

“If you think about it, she voted for criminal aliens against veterans,” he said, claiming Rosen was in favor of so-called sanctuary cities and has not supported military veterans.

He, as he often does with Democratic candidates, tried to tie Rosen to her party’s congressional leaders, who are unpopular with GOP voters.

Trump called Heller on to the stage, where he hailed the president’s time in office.

“Mr. President, it’s a pleasure to work with you and putting Nevada back to work,” Heller said, while hailing the state of the economy.

Trump continued heaping praise on Heller after he left the stage, saying he had been a “champion” for conservative causes and helping military veterans.

The president urged the raucous and friendly crowd to get out to the polls on Election Day, yet another sign that he views the coming midterms as a turnout battle.

“You got to get out for the midterms,” Trump roared. “Don’t be complacent. … It’s like, if someone has a cold, we don’t have a majority.”

And in an apparent reference to his hotel in Sin City, Trump told the crowd he has a “bias for this area.” On Wednesday, while visiting the hurricane-soaked Carolinas, he made a reference to the Lake Norman area near Charlotte; he owns a golf resort on the banks of the massive lake.

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In a statement after Trump’s appearance, Rosen said, “President Trump came back to Nevada to fundraise for my opponent and attack me with petty insults because he knows Dean Heller will be his rubber stamp in the Senate, and I won’t. Nevada’s hardworking families deserve an independent voice in the Senate who will fight for them and put our state first, not a spineless politician who breaks his promises under pressure from the White House and votes to take away health care from his constituents.”

The statement also highlighted that Trump said he and “Senator Heller love each other,” that he can “always count on Dean Heller’s vote,” and that he has had “no better friend in Congress than Dean Heller.”

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For Trump, the stakes this election are about as high they come. That’s because Democratic control of the House could bring impeachment proceedings — especially if special counsel Robert S. Mueller III issues a report showing either coordination by Russia and the Trump campaign or obstruction of justice by the president. Or both.

At another rally in Montana earlier this month, Trump told supporters if Democrats take the House and move to impeach him, “it’s your fault … because you didn’t go out to vote.”

That makes the 3rd District seat crucial for the president. Tarkanian is in a tight race with Democrat Susie Lee. Inside Elections with Nathan L. Gonzales rates the contest Tilts Democratic.

Heller is in a dogfight with Rosen, which Inside Election rates a Toss-up. Several recent polls have given Rosen a lead no higher than 2 percentage points; another gave Heller a 1-point point advantage less than seven weeks from Election Day.