Five things you need to know about President Trump's campaign rally Tuesday night in Phoenix:

Governor not going: A Trump campaign official told 12 News Sunday that Republican Gov. Doug Ducey won't be at the rally for the Republican president.

"Ducey is choosing not to attend, but he will be greeting the president's airplane, along with the (Arizona) congressional delegation, when it lands," said the Trump campaign official, who requested anonymity.

UPDATE: Ducey spokesman Daniel Scarpinato issued this statement Monday on why the governor's not going to the rally:

The governor looks forward to welcoming President Trump to Arizona when he arrives at the airport. Gov. Ducey's focus has been working with law enforcement toward a safe event in downtown Phoenix for all those involved and in the area. That will continue to be his priority during the event and afterwards.

Trump visited the state seven times during the presidential campaign. Ducey appeared just once at a Trump rally, in August 2016 in Phoenix, without Trump on the stage.

Arpaio's not going, either: Former Maricopa County Sheriff Joe Arpaio told 12 News Monday that he won't be attending the rally.

"If they don't want me there, I won't be there," the sheriff said in an interview Monday. "My wife and I will watch it at home on Channel 12."

A Trump pardon of Arpaio at the rally is widely viewed as the spark that could ignite violent protests.

A pardon would let Arpaio off the hook for any punishment after he was found guilty of intentionally ignoring a court order.

The 85-year-old Arpaio, an immigration hardliner whose endorsement bolstered Trump's credibility on the issue, faces up to six months in jail when he's sentenced in October

Behind-the-scenes concerns: The governor's been quiet in public about the rally, but sources tell 12 News there has been concern behind the scenes. Ducey's office has looked at possible alternatives to the rally, according to sources familiar with those efforts.

Scarpinato said the governor's "entire focus is making sure the rally is safe."

Concerns at White House, too: New York Times White House reporter Glenn Thrush tweeted over the weekend about Arizona jitters at the White House:

The Times on Sunday reported that White House officials "are bracing for a furious reception."

Police unveil security plan: Phoenix police, who are leading the security for the event, are expected to brief the media Monday on what to expect around the rally venue.

The Phoenix Convention Center halls booked for the rally can hold more than 10,000 people. Thousands more are expected to protest outside the downtown Phoenix building.

12 News has learned that security planners are also preparing for protesters who might try to topple the Confederate monument at the Capitol or shut down Interstate 10 through downtown Phoenix.

READ: Phoenix PD monitoring social media, mapping problem spots in prep for Trump rally

There is also concern about possible confrontations on light rail lines downtown as protesters disperse.