PHOENIX — Republican Kari Lake and Democratic Rep. Ruben Gallego faced off in Arizona’s feisty first and only Senate debate Wednesday evening, trading shots over the border, abortion, tax policy and more.

The barbs started before the moderators even asked a single question.

“We are at a crossroads, Arizona,” Gallego said in his opening statement, highlighting Lake’s repeated election denialism. “We’re going to see and talk to somebody who has really failed the basic test of honesty.”

Lake shot back: “Tonight, we’re going to watch as somebody tries to reinvent himself. Somebody who used to be a member of the Progressive Caucus, somebody who has destroyed the very congressional district that he has served for the past 10 years.”

As the candidates bounced from topic to topic over an hour onstage, the answers circled back on a key slice of voters: old-line Republicans and independents who aren’t necessarily comfortable with Lake. Gallego continually referred to his support from prominent Arizona Republicans, while Lake repeatedly brought up former President Donald Trump as she tries to prevent Trump voters from crossing over in the Senate race.

“Border mayors that used to campaign with her are now campaigning with me because they don’t think that she’s serious about this,” Gallego said at one point. He added: “It seems like Donald Trump doesn’t want to campaign with her anymore, either. He’s not allowing her pictures on any of his billboards. So this is what we’re seeing right now, a candidate that could only talk but doesn’t actually produce results.”

Lake, who name-dropped Trump several times throughout the debate, quickly replied.

“President Trump, my good friend, has called me ‘border Kari,’” Lake said. “I love the nickname, and I’m going to go there to Washington, D.C., and help him build that border wall and secure the border.”

A massive campaign bus parked outside the debate had a large image of Trump and Lake together with large print touting his endorsement of her. Campaign signs across Phoenix also feature photos of Lake and Trump, reading, “Trump endorsed!”

Gallego, in contrast, didn’t mention Vice President Kamala Harris by name during the debate. In an interview with NBC News earlier in the week, he said he was running “independently” of Harris. He hasn’t attended most of her campaign events and visits to the state.

The issues looming large throughout the race have been immigration and border security, a central topic for Arizona, which shares its southern border with Mexico. On Wednesday evening, those topics were once again in the spotlight as the moderators spent nearly half of the 60-minute debate on the issue.

“A community that doesn’t have border control is not a country,” Gallego said when he was asked whether he supports open borders. “Absolutely not.”

Lake’s rebuttal focused on Laken Riley, the 22-year-old college student alleged to have been killed by an undocumented immigrant in Georgia, to drive home the importance of the border. “We want to be able to go for a jog in the morning like Laken Riley did and not have to worry about being killed, raped and murdered,” she said.

Lake reiterated her position in an interview this week with NBC News, saying she didn’t support any component of the bipartisan border security bill — and falsely claiming that the legislation “sent $115 billion overseas to kill people.”

“The senators were not bipartisan,” Lake said misleadingly of the trio largely behind the bill. The bipartisan legislation was negotiated by retiring independent Sen. Kyrsten Sinema — whose open seat Lake is vying for — along with Democratic Sen. Chris Murphy of Connecticut and GOP Sen. James Lankford of Oklahoma.

Lake has long made the border a cornerstone of her campaign, chastising Gallego for supporting the Biden-Harris administration’s immigration policies. Gallego, in turn, has made the bipartisan border bill that Trump and Lake opposed a big part of his campaign.

“The compromise bill that was supported by Border Patrol, and Kari Lake, for still no reason she can explain it, she can’t explain it, why she was against the bill,” he fired back.

At the halfway point, the moderators shifted the discussion to abortion. With early voting already underway in the state, Arizonans will vote on Proposition 139, a proposed state constitutional amendment that would enshrine abortion rights through fetal viability.

Gallego brought up Lake’s flip-flop on Arizona’s since-repealed 1864 abortion ban, which would have banned all abortions with no exceptions for rape or incest. “She said it was a great law,” he said, noting Lake’s comments about the 1864 ban during her 2022 bid for governor. During her Senate bid, Lake came out against it.

“I want to make sure UVF is protected,” said Lake, most likely referring to in vitro fertilization or IVF, a fertility treatment that has become the latest front in the political battle over reproductive rights.

“He acts like he cares about us,” Lake said of Gallego, “speaking directly to the women” watching the debate.

Both candidates have been reminding their would-be constituents for months about each other’s past. For Lake, it’s pinning Gallego to his progressive past. For Gallego, it’s highlighting Lake’s ardent election denialism after the 2020 presidential race and the 2022 race for governor, which she lost to Democrat Katie Hobbs.

Asked to say “once and for all” that she lost her race, over which she launched unsuccessful lawsuits, Lake instead referred to a previous question about Arizona’s water crisis and said, “Can I talk about water?”

After the debate, the Lake campaign sent several surrogates to tell reporters that she "won" the debate and appeared strong, while Gallego appeared "weak."

Talking to the media immediately after the debate, Gallego said: “She needs to be loud, she needs to lie because she’s weak. That’s it. The weaker you are, the louder you are.”