President Trump landed the first blow at his rally next Tuesday five days early - with a tweet at 3:56 a.m. Thursday.

One of Trump's missions next year is firing Arizona Sen. Jeff Flake, the president's toughest GOP critic when he was a candidate, now the author of a new book that raises questions about Trump's mental stability.

Trump's been shopping for an Arizona Senate candidate to endorse for 2018.

His apparent blessing of Flake primary opponent Kelli Ward, a former state senator who's been hungering for Trump's attention since her losing race against Sen. John McCain last year, might signal she's the chosen one.

But Ward's team hasn't confirmed an endorsement or that she'll have a prominent role at next week's rally.

This might be why: A few hours after Trump's tweet, there were reports that the president's aides were surprised by it. They doubt she can win.

The story also floated the notion that Trump allies were wooing former Arizona Congressman Matt Salmon, now a top official at Arizona State University.

Salmon quickly shot that down: "Love my job at ASU. No interest in Flake race," he said via text message.

State Treasurer Jeff DeWit, who was a top executive with the Trump campaign and one of the first elected officials to endorse him, has long been rumored as a potential Flake challenger.

But DeWit told me this week that no one has spoken to him about taking on Flake.

Later in the day, Flake allies came to his defense.

Senate Majority Leader Mitch McConnell issued this statement: "Jeff Flake is an excellent senator and a tireless advocate for Arizona and our nation. He has my full support."

About that 'toxic' Trump tweet

It's not unusual for Trump to tweet a reaction to something he just saw on Fox News.

In this case, his tweet about "toxic" Jeff Flake appeared to borrow the same word used by former Arizona Congressman J.D. Hayworth, according to Arizona Politics blogger Mitch Martinson.

Just 35 minutes before Trump used the adjective, Hayworth pinned the same label on Flake, on "Fox & Friends."

"Jeff has done his best to be obnoxious, to be the smirking senator that he's really known to be," Hayworth said.

Hmm, JD Hayworth for U.S. Senate?

Pardon us, but ...

Three of Arizona's four Democratic members of the House - Congressmen Ruben Gallego, Raul Grijalva and Tom O'Halleran - are telling President Trump, "Pardon us, but … "

Their letter to the president Thursday urges him not to pardon former Sheriff Joe Arpaio. They say a pardon would send a "clear message that your allies are immune from prosecution."

Arpaio faces up to six months in prison when he's sentenced in October for intentionally ignoring a federal court order. Trump has said he's seriously considering a pardon; it could come at the rally Tuesday.

Congresswoman Kyrsten Sinema is the other Democrat in the Arizona delegation.

She didn't sign the letter, but did issue this statement about Arpaio to 12 News:

"Former Sheriff Joe Arpaio hurt Arizonans and cost taxpayers a great amount of grief and money. He must be held accountable for his actions. No one is above the law."

Sinema is expected to announce her own run for the U.S. Senate within the next several weeks.

The show must go on …

That's the word from the Trump campaign about Phoenix Mayor Greg Stanton's appeal to postpone the rally.

Stanton says the event's coming too close to the violent weekend in Charlottesville.

The Trump campaign told a reporter that barring any unforeseen events, there's "no chance" the rally will be postponed.

Trump calling on the base

The president's daughter-in-law Lara Trump is making robocalls to GOP voters in the Valley, promising them an "incredible experience" at Tuesday's rally.

The campaign is also airing radio ads to help fill Phoenix convention center halls that hold about 10,000 people.

It is exceptionally rare for a sitting president to advertise for people to attend a local rally.

We're hearing from Democrats and independents who are also getting the calls. It's likely the campaign is using outdated voter rolls.