President Donald Trump's 2020 campaign is scouting a Phoenix Convention Center site for a possible rally the week of Aug. 21, according to a convention center spokesman.

The convention center gave the Trump campaign information Tuesday on rooms that could hold several thousand people, but has not heard back, said the convention center's Jerry Harper.

It would be Trump's first visit to Arizona since winning the election last year.

Trump made seven campaign stops in Arizona in 2015 and '16, the last one at the Phoenix Convention Center just two weeks before the November election.

Trump defeated Democrat Hillary Clinton by 3.5 percentage points, but he would be returning to a state where he faces several challenges:

-Arizona's junior senator, Republican Jeff Flake, wrote a new book ripping Trump as "volatile" and "unpredictable." The book expands on Flake's criticism of Trump during the presidential campaign. Trump reportedly has pledged to spend $10 million to block Flake's bid for re-election next year.

-Arizona's senior senator, Republican John McCain, voted down the Senate GOP's Obamacare repeal, virtually ending Trump's hopes of fulfilling a major campaign pledge this year. McCain also wrote his own strategy for the war in Afghanistan, because the president had failed to do so.

-Trump's approval ratings among Arizona voters are underwater. In a recent survey, 44 percent approved of his performance, 53 percent disapproved.

-The same survey shows 65 percent of Arizona Republicans still support Trump.