WASHINGTON — President Trump wrote a Twitter post Saturday aimed at state officials state resisting a broad request for data by his voter-fraud commission, including officials from deeply Republican states whose support the controversy-laden White House can ill afford to lose.

“What are they trying to hide?” Trump wrote of officials from states that have questioned the panel’s request. Indiana, home of Vice President Mike Pence, and Mississippi, a state that voted overwhelmingly for Trump last year, are among those states.

Trump’s taunt may have been meant to counter a backlash that could effectively scuttle much of the work of Presidential Advisory Commission on Voter Integrity before it begins. Members of the commission said they planned to compare the state records to databases of undocumented immigrants and legal foreigners to determine if large numbers of unqualified voters are participating in U.S. elections.

Deploying sometimes colorful language, state officials have called the panel’s request for data that includes partial Social Security numbers inappropriate, and said they wouldn’t comply or would provide only information that was already publicly available.

While the data request resonates with long-held Republican claims of illegal voting, the commission – and by extension, the White House – is on what usually sympathetic state officials say is the wrong side of the issue of states’ rights.

The timing could hardly be worse. Saturday’s Twitter post capped a week during which Trump twice picked fights that alienated badly needed Republican allies. He supported ads against Sen. Dean Heller, the Nevada Republican who refused to support the Senate’s health care bill, and then used unusually course language to berate MSNBC host Mika Brzezinski. Those comments were condemned by a range of prominent Republicans, including two female senators whose support is crucial to passing the Senate’s bill to repeal and replace the Affordable Care Act.

On Friday, White House spokeswoman Sarah Huckabee Sanders said the refusal by state officials to comply was “mostly a political stunt” and that the commission is asking for publicly available data.

But many secretaries of state appeared to view the request differently.

North Carolina officials said in a statement that they’ll comply only with requests for public information and won’t turn over partial Social Security numbers, driver’s license numbers or dates of birth, which are confidential under certain state or federal laws.

In Oklahoma, which Trump won in November by 36 percentage points over Democrat Hillary Clinton, election officials plan to hand over publicly available voter rolls but won’t comply with requests for partial Social Security numbers.

Several other states announced that the president’s panel will get more limited data and would also have to pay for it, the way political campaigns do.

Virginia Gov. Terry McAuliffe, a Democrat, said in a statement that he has “no intention of honoring this request,” and questioned the panel’s motives. The commission “at worse is a tool to commit large-scale voter suppression,” McAuliffe said.

Sen. Dianne Feinstein of California, the top Democrat on the Senate Judiciary Committee, said in a statement that she was “alarmed” at the request by the “so-called voter-fraud commission” for personal data and voting history “with absolutely no legal basis for doing so.”