The national terrain Donald Trump is tiptoeing around on Tuesday night in Phoenix, during his first high-profile appearance since going on vacation and voicing support for white nationalists in Charlottesville, continues to be slippery at best for the president. He his, of course, historically unpopular with the American people overall, but more crucially his support continues to erode outside of his hardcore base and that includes slipping numbers within the Republican Party, where one-in-four now disapproves of the job Trump is doing. On Tuesday, the White House appears set to allow the president let his hair down and “let Trump be Trump” to a city and state that recent polling shows isn’t quite so sure it wants a Trumpier Trump.

A new HighGround poll out this week finds 55 percent of the traditionally red state disapproves of the job Trump is doing. This is not a good sign for Trump or the GOP considering the president underperformed in November, pulling in only 48 percent of the vote, beating Hillary Clinton by a slim 3 point margin. The ditch Trump has dug himself is particularly daunting considering that to claw back some of that support he’ll need to win over independent and unaffiliated voters in the state. Currently, Trump’s approval rating among independents in Arizona stands at a dismal 27 percent and 33 percent among unaffiliated voters.

“If the President and the GOP fail to expand public support beyond the GOP base, the party may face historic electoral failures in 2018,” said Chuck Coughlin, President and CEO of HighGround Public Affairs said in a statement Monday. “While I am sure he will receive a hero’s welcome inside the Convention hall tomorrow, there should be little doubt given this research, which shows that he enjoys single digit support amongst Democrats and less than a third of Independent and unaffiliated voters, that this is not a sustainable general election coalition.”

The state’s senators have reflected this unease with Trump’s performance so far, with Sen. John McCain and Sen. Jeff Flake stoking the GOP’s often-insufficient outrage at the things that Trump thinks, and says, and does. Trump’s coattails have shrunk significantly enough that Arizona’s Republican governor Doug Ducey has chosen to skip the event altogether. During the 2016 campaign, while the Hillary Clinton campaign may have been a bit optimistic in its decision to contest Arizona, the state sufficiently wavered in its GOP support to make the state a battleground on the electoral map.

On Tuesday, we’ll see which Trump shows up, but time and again the president has shown himself incapable of changing political speeds. Charging full speed ahead plays well to Trump’s base and suits his disposition, but a Trumped up version of the president has so far turned off more voters in Arizona than it has appealed to. If that continues in a state that the GOP has long considered a gimme, for Republicans with an eye on 2018, that could spell serious trouble.