Fresh off a rally in Tulsa, Okla., in which nearly two-thirds of the arena was empty, President Trump heads to Arizona for a series of smaller events centered on a key element of his reelection pitch: border security.

The president is scheduled to survey part of the border fence with Mexico in Yuma, Ariz., on Tuesday.

"The president will then participate in a roundtable discussion with local community and elected leaders on border security," a White House official told NPR. "After the roundtable, the President will tour the wall and thank Border Patrol and law enforcement for their tireless efforts."

Trump will be joined by Chad Wolf, acting secretary of the Department of Homeland Security; Ken Cuccinelli, the acting deputy DHS secretary; and Mark Morgan, acting commissioner of Customs and Border Protection.

Trump will then travel to Phoenix to deliver remarks at a Students for Trump rally at Dream City Church, hosted through Turning Point Action, a pro-Trump group.

The church, which can hold about 3,000 people, released a statement saying it only found out that Trump would be speaking at the event after it agreed to rent its facilities.

"Dream City's facility rental does not constitute endorsement of the opinions of its renters," the statement said.

Coronavirus concerns

Arizona has seen a spike in cases of the coronavirus recently, and Phoenix has joined several cities across the state in requiring residents to wear masks in public spaces.

Phoenix Mayor Kate Gallego said she's concerned about the president's trip.

"We are actually seeing the fastest rate of growth among our young people in the community, and here it is, a rally specifically focused on that demographic," she told CNN. "Public health professionals in Phoenix are trying to tell young people to take this seriously."

Students for Trump includes a waiver similar to the one the Trump campaign gave to attendees of the Tulsa rally, acknowledging the health risks.

"By attending this convention, you and any guest voluntarily assume all risks related to exposure to COVID-19 and agree not to hold Turning Point Action, their affiliates, Dream City Church, employees, agents, contractors, or volunteers liable for any illness or injury," it reads.

A changing state

Tuesday marks Trump's third trip this year to this once-red, now purple state. He hosted a rally in Phoenix in February and visited a mask-making facility in May.

Trump won Arizona by 3.5 percentage points in 2016, a far cry from Mitt Romney's 10-point victory over President Barack Obama in 2012.

Democrats regard it as a critical 2020 battleground state and are closely watching its Senate race between Republican incumbent Martha McSally and Democrat Mark Kelly, a former astronaut and husband of former Rep. Gabby Giffords. Kelly has been leading in the polls, but the race is still considered a toss-up.

Gov. Doug Ducey appointed McSally to her seat following her loss during the Senate campaign to then-Democratic Rep. Kyrsten Sinema.

Nearly a third of the electorate in Arizona don't belong to either major political party, but Democrats are hopeful that a growing Latino population will translate to a shift in November.

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