Large protests are expected near President Trump’s rally in downtown Phoenix on Tuesday night, his first such event since he drew wide condemnation for his comments on the violence in Charlottesville, Va., this month.

The rally, scheduled for 7 p.m. local time at the Phoenix Convention Center, is Mr. Trump’s first visit as president to Arizona, where he made fiery remarks on a signature issue — immigration — during his election campaign last year.

The state is home to high-profile supporters of Mr. Trump, like Joe Arpaio, the former sheriff of Maricopa County who built a national reputation on his hard-line stance against undocumented immigrants and was recently convicted of criminal contempt of court. But it is also home to staunch critics of Mr. Trump, like Senators Jeff Flake and John McCain, both Republicans who have feuded openly with the president.

Amid the fallout from Mr. Trump’s assertion that “both sides” were to blame for the violent clashes in Charlottesville, and following the president’s suggestion that he could pardon Mr. Arpaio, Phoenix is bracing for throngs of protesters to come out in 100-degree heat.

Here are answers to some of the questions ahead of the event.

Who is planning to protest?

Several opposition rallies and marches have been planned, according to the Arizona Republic. By Tuesday, more than 3,900 people had indicated on Facebook that they would attend one event, Protest Trump Downtown Phoenix, across the street from the convention center. Another 2,700 said they planned to attend White Supremacy Will Not Be Pardoned, organized by the Puente Human Rights Movement.

Another rally, Never Again: Jews and Allies Against Hate, was planned by David Schapira, a Tempe city councilman, and State Senator Robert Meza for the State Capitol earlier in the afternoon. A church in Phoenix also scheduled a march from the convention center to the Capitol Tuesday evening.

The Phoenix New Times reported that one group associated with the anti-fascist, or antifa, movement had called for “an anti-fascist & anti-colonial contingent against Trump’s rally” on Tuesday.

The Republic reported that events were also planned in support of Mr. Trump, including a Young Republicans meetup and a motorcycle ride.

Jeri Williams, the police chief in Phoenix, said in a statement that the department would have “maximum staffing” during the rally and was working “24/7” to prepare for it.

How are local officials responding?

The mayor of Phoenix, Greg Stanton, a Democrat, has urged Mr. Trump to delay his trip.

“America is hurting,” Mr. Stanton wrote Monday, in an opinion piece for the Washington Post. “And it is hurting largely because Trump has doused racial tensions with gasoline. With his planned visit to Phoenix on Tuesday, I fear the president may be looking to light a match.”

Gov. Doug Ducey, a Republican, was planning to greet Mr. Trump but not to attend the rally, according to the Arizona Republic.

Neither Mr. Flake nor Mr. McCain, both of whom last week tweeted about their apparent disapproval of Mr. Trump’s comments on Charlottesville, is expected to attend. Mr. Trump called Mr. Flake, who is up for re-election next year, “toxic,” and praised the senator’s primary opponent on Twitter last week. And, during the same news conference when he commented at length on Charlottesville, Mr. Trump took a jab at Mr. McCain, who derailed the Republican health care bill with a dramatic thumb-down vote on the Senate floor last month: “You mean Senator McCain who voted against us getting good health care?”

Is Mr. Trump going to pardon Mr. Arpaio?

Nothing has been officially announced. Mr. Trump has discussed a pardon for Mr. Arpaio, according to an associate of the president who spoke with The New York Times, and told a Fox News reporter that he was “seriously considering” it. But some of his advisers are concerned that such a move would add fuel to the firestorm surrounding the president’s recent comments about race and further divide the country.

Mr. Arpaio, who was ousted by voters in November, frequently employed anti-immigrant rhetoric and was one of Mr. Trump’s most loyal supporters on the campaign trail. Earlier this summer, a federal judge ruled Mr. Arpaio had committed a crime by refusing to stop detaining suspected undocumented immigrants despite a court order. He faces up to six months in prison and is to be sentenced in the fall.

Mr. Arpaio said on Monday night that he would not attend the rally.

Did Arizona vote for Mr. Trump?

Mr. Trump won Arizona somewhat narrowly, with 48.1 percent of the state’s vote compared with 44.6 percent won by Hillary Clinton. Republican presidential candidates have previously claimed the state with wider margins of victory — Mitt Romney won it by 10.1 percentage points in 2012, and Mr. McCain won by 8.8 points in 2008 — but the state has edged more Democratic as its Latino population has grown.