What does Ruben Gallego know about Arizona that Kamala Harris doesn’t?

Republicans had been here before, with Sinema. In 2018, the retiring senator won her first term by massively outspending then-Sen. Martha McSally and moving to the middle early, pre-empting attacks on her past as a Green Party activist and sharp-tongued progressive. They hammered Sinema for calling Arizona “the meth lab of democracy” at a left-wing conference, when both she and Gallego were attacking SB1070, a Republican-passed law designed to push out illegal immigrants.

Sinema, who opted not to run for a new term as an independent, is ending her career as the sponsor of the Senate’s border security bill — a linchpin of both the Harris and the Gallego campaigns. Lake has called this a ruse, using the phrase “extreme makeover” five times in their debate to accuse him of an election-year conversion.

“He called it the dumb, stupid border wall. He wrote an op-ed that said why we should never build Trump’s wall ever,” she said. “The only piece of legislation that Mr. Gallego has put forth was not about border security; it was about removing the word illegal alien from anything in the federal government paperwork.”

Gallego had changed — crucially, before most voters were paying attention to the race. In 2019, he endorsed Harris’ primary campaign, when she was taking progressive stances that have been set aside this year. But he left the Congressional Progressive Caucus as he ran for Senate; in a prime time speech at the Democratic National Convention, he introduced a group of fellow veterans and called John McCain a “hero.”

Republicans knew that Gallego would emphasize that he served in the Marines and fought in Iraq; they did not anticipate that he’d campaign alongside McCain’s son, or face no real pressure from his party’s left after he went on “Real Time with Bill Maher” and begged activists to stop saying “Latinx” when they meant “Latino.” On Thursday, as Lake and Gallego entered the debate studio on Phoenix’s northern outskirts, the Green Party’s nominee and a few supporters marched outside, largely ignored by reporters.

“Those are DC terms,” Gallego said after the debate, when a reporter asked if he still considered himself a progressive. “Those DC terms just don’t really matter in Arizona.”

Republicans did know that their primary voters would nominate Lake, whose confident, media-bashing 2022 campaign for governor ended with a narrow loss and a refusal to concede. The national party, which is spending for Lake, has prioritized more promising Senate races in Montana and the Midwest. And her effort to portray Gallego as an election-year centrist was complicated after the Dobbs decision: No clip of the Democrat was as potent as the footage of Lake, pre-Dobbs, praising Arizona’s “great law” that banned abortion outright.

Lake now supports the 15-week abortion ban that went into effect after Dobbs, and opposes Proposition 139, which would write abortion rights into the state constitution and leads overwhelmingly in polls.

“I like the law we have on the books,” Lake told reporters on Thursday, after casting her early vote, and walking over to a campaign bus decorated by an image of her and Trump together.

Democrats see Lake as a diminished figure — competitive with Gallego, but weaker than the top of the ticket, and lacking Trump’s appeal to the share of Latino voters who credit him with economic growth and border security. “She’s a Trump tribute act,” said former state Rep. Lorenzo Sierra.

At the early voting site, Lake refused to take a question from a Reuters reporter (“I had a really unfair interview”), then posed for a selfie with a fan who said that the Biden administration’s spin around Hurricane Helene was worthy of Joseph Goebbels. “These are the agents of misinformation,” said Lake, pointing at the media’s cameras. And on Sunday, Trump would be back in Arizona to help.

You don’t need to overthink the polling gap between Harris and Democratic Senate candidates in key states. In most states where that’s playing out — Nevada, Montana, Ohio, Pennsylvania — the Democratic nominee has been on the ballot for years, and defined him or herself before Republicans could.

Gallego stands out because he had not done that work statewide until last year. He had looked at potential Senate runs in 2018 and 2020, and both times, he stepped aside for Democrats who had more centrist images: Sinema and Sen. Mark Kelly. In 2021, when progressive groups started looking for a challenger who’d push Sinema left, or beat her, they immediately backed Gallego.

That meant that the congressman, already well-liked in the party, had credibility with the base — without doing anything new to keep it. And it gave him years to update his image and positions, co-sponsoring immigration bills with Republicans, endorsing the Biden administration’s most popular economic wins, and breaking with left-wing activists whose opposition to the border wall and deportations was politically toxic. One of Lake’s weaker moments at the debate came when she challenged Gallego to say whether he’d deport anyone; he said that he would.

“What I was against was him putting up a fence or a border wall from San Diego to Laredo without any thought about where it’s needed, whether or not he needed to have manpower and technology behind it,” Gallego said. “Putting up a wall that you can’t afford to maintain is not going to end up making us more secure.”

This overlaps with Harris’ positioning. But she was not as well known in Arizona; she did not have Gallego’s military record as an ice-breaker with skeptical swing voters; and she had to make these transitions after being part of an administration that has been effectively attacked by Republicans for a years-long surge of asylum seekers at the border.

It’s possible it’s too late for Democrats to make Gallego’s formula work at the national level this year. But if he pulls it off and Harris falls short against Trump, don’t be surprised if some Democrats come asking him to do it for them on a presidential ticket in 2028.