Candidates running for Senate in Arizona are putting daylight between themselves and President Biden on immigration as Title 42, which gave border officials authority to expel migrants without screening for asylum, is set to expire.

Democratic Senate candidate Rep. Ruben Gallego (Ariz.) accused the Biden administration of being unprepared to handle the surge of migrants in four letters addressed to Biden and other officials last week, while incumbent Sen. Kyrsten Sinema (I-Ariz.) warned of a “humanitarian crisis” when the policy expires later this week.

“Everyone here in Arizona knows we are not prepared. The Biden administration had two years to prepare for this and did not do so. And our state is going to bear the brunt and migrants will be in crisis as soon as next week. It will be a humanitarian crisis because we are not prepared,” Sinema told CBS’s Margaret Brennan in an interview for “Face the Nation.”

The comments come as Republicans seek to hit Biden and his Democratic allies on immigration going into next year’s general election.

“Not only is [immigration] on the rise but also with this latest news, I think it’s going to be one of the most dominant issues in the Senate race as we march toward Election Day,” said Mike Noble, chief of research at the Arizona-based polling firm OH Predictive Insights.

House Republicans are planning to pass a border crackdown bill on the same day Title 42 expires, hoping to draw a stark contrast with a Biden administration struggling to manage a post-Title 42 border.

The House bill is still facing some internal GOP dissent, but it’s far more advanced than any similar measure in the Senate.

In the lead-up to Thursday’s deadline, Sinema and Sen. Thom Tillis (R-N.C.) gave new airtime to a proposal they’ve billed as an extension of Title 42 that would grant extraordinary powers to U.S. border authorities.

It’s not just lawmakers in Washington who are criticizing the administration over Title 42’s end.

In Arizona, Democratic Gov. Katie Hobbs called on the federal government to provide more support to the state as the policy nears its expiration date. 

“For the past three years, the federal government has used Title 42 as a temporary solution to a permanent problem,” Hobbs said during a press conference on Monday. “I’m afraid these challenges will only get worse. And I’m afraid the federal government is unprepared to meet the demands of the expected influx.”

The generalized panic over Title 42 has become increasingly apparent in Washington and border communities, though it’s unclear how much or for how long crossings will rise after the policy ends.

Gallego, a progressive running in a purple state, jumped into the debate with four letters addressed to President Biden, Homeland Security Secretary Alejandro Mayorkas, Federal Emergency Management Agency (FEMA) Administrator Deanne Criswell, and Reps. Kay Granger (R-Texas) and Rosa DeLauro (D-Conn.), the heads of the House Appropriations Committee.

“I have heard repeated concerns about a lack of information around federal government policy that directly impacts Arizonans, our communities, and our local economies,” Gallego wrote. 

“That includes limited notification of what resources and Department of Defense personnel will be sent to their area.”

Gallego’s move to distance himself from the administration makes sense politically given Biden’s weak standing in the swing state. According to a Morning Consult survey released last month, the president has a 40 percent approval rating and a 57 percent disapproval rating in the state. Among Arizona’s independent voters, only 29 percent said they approved of Biden’s job performance. 

Polls also show voters souring on Biden’s handling of immigration. According to a Global Strategy Group poll released last month, 58 percent of voters from seven swing states, including Arizona, said they disapproved of how Biden was handling immigration, while only 32 percent said they approved. 

“Gallego has absolutely tried to distance himself, but that’s where it’s kind of incumbent upon Sinema or even the Republican out there to tie that around him and say, ‘Hey, that’s your party,’” Noble said. “Their administration is currently hands on the wheel. But I think [it’s] good news for Sinema to wrap something around Gallego.” 

Sinema, on the other hand, has continued to beat the drum against the Biden administration on the issue. 

“The only candidate who didn’t have to start distancing herself from the administration on this issue was Sen. Sinema,” said Stacy Pearson, an Arizona-based Democratic strategist. “It’s going to be a critical issue in Arizona.” 

Arizona’s Senate race is slated to be one of the most closely watched races in the country next year, given Sinema’s exit from the Democratic Party and the nature of the state. The nonpartisan Cook Political Report and the University of Virginia’s Sabato’s Crystal Ball both rate the contest as a “toss-up.” 

While Democrats swept the state’s statewide elections last year, Arizona still has a Republican streak, with the GOP controlling both state legislature branches. 

“Despite having elected Democrats to many of the major statewide offices from Senate to governor and elsewhere, we’re still a Republican-majority state. We’re not a blue state,” Pearson said. “It certainly shows a contrast between partisan politics and Arizona politics.” 

Navigating that partisan divide is trickier for Gallego because he’s still a Democrat who’s better off not breaking fully from the White House.

And Democrats are generally pursuing a more complicated message on the border and immigration, touting border controls but also a willingness to create legal pathways for immigration.

“To say that you want people going there through a legal orderly fashion, where you have Border Patrol agents, you have more judges to process asylum, that you have more folks at the border to process [migrants], that’s a positive, good thing. Those are things that you should be for,” said Kristian Ramos, a Democratic strategist.

Sinema’s legislative proposal with Tillis, though billed as a moderate bipartisan compromise, has generally been met with disdain from immigrant advocates and border policy experts.

America’s Voice, a progressive immigration advocacy group, wrote in a recent release that the Sinema and Tillis bill “replaces a balanced approach with a set of punitive policies that should be complete non-starters in the Democratically controlled Senate.”

But Gallego and Sinema are battling for Arizona’s independent voters, placing different bets on where that group’s sentiments on the border and immigration lie.

Although Gallego has more constraints on how far he can stray from the Democratic base position, he has structural advantages over Sinema as the likely Democratic nominee.

And Sinema’s electorate is likely to shrink as Gallego and the eventual GOP nominee activate their respective bases.

“Given recent polling, she’ll be hard-pressed to put together a winning coalition in a three-way race,” said Ramos.