WASHINGTON (AP) — A dozen big-name business leaders, including lifelong Republicans and independents, say they won't support real estate mogul Donald Trump for president. They say he would be bad for the economy, and they question how successful he's been as a businessman.

"For sustained investment, economic growth and job creation, American business needs as much predictability, reliability and stability in our government as possible," they write. "Donald Trump is simply too reckless for American business."

A copy of the letter was given to The Associated Press ahead of the group's push for others to sign on, as well as the release of the group's new website on Friday. It comes on the heels of an open letter by more than 30 former GOP members of Congress condemning the Republican presidential nominee as "disgraceful."

Signatories of the latest letter include Wikipedia founder Jimmy Wales, famed chef Jose Andres and Carlos Gutierrez, U.S. secretary of Commerce under President George W. Bush and the former chief executive officer of the Kellogg Company. Andres is tussling with Trump over his decision to pull his planned restaurant out of Trump's new hotel at the Old Post Office in Washington.

Jack McGregor said he hopes the effort convinces undecided voters to choose Democrat Hillary Clinton. He's a Republican former Pennsylvania state senator and founder of the National Hockey League team the Pittsburgh Penguins.

"I believe we can reach thinking Republicans like the ones I served with in Pennsylvania," he said.

The group came together as John Stubbs, who has been organizing Republicans who back Clinton, realized that business leaders — of all political persuasions — have particular concerns about a Trump presidency, Stubbs said.

A former Republican staffer in Washington, Stubbs said he has not been working with the Clinton campaign.

Trump has many business leaders in his corner. Some of his highest profile supporters include investor Carl Icahn, financier T. Boone Pickens and PayPal co-founder Peter Thiel.

The anti-Trump letter makes a two-front case against the Republican nominee. They say he has not been particularly successful in his decades in real estate. And they believe he is offensive and dangerously erratic.

"Trump's harmful rhetoric regarding immigrants, women, racial and religious minorities, the disabled and American veterans is not only unacceptable, it creates an atmosphere of vulgarity that poisons the climate, as does his general approach to business and many of his economic ideas," they write. "And how do you lose nearly a billion dollars in a single year?"

The New York Times said it obtained several pages of Trump's 1995 state income tax filings that showed he took a net loss of $915,729,293 in federal taxable income for the year.

The letter cites Trump's businesses' six business bankruptcies, several thousand lawsuits and repeated failure to pay subcontractors as evidence that he's not a successful businessman.

"This approach is anathema to Democrats and Republicans alike," said Bill Cummings, who also signed the letter. Cummings is the founder of a Boston-based commercial real estate company.

Sara Sutton Fell, another letter-signer and the Colorado-based founder of the employment search firm FlexJobs, said she wouldn't be able to sleep at night running her company as Trump runs his.

"The fact that he's running on his business skills is terrifying," she said.