Broadway Cares is among those who have cancelled a fundraiser at the New York property.
She hit the GOP field on immigration and the Loretta Lynch confirmation fight.
Jeb Bush, another 2016 contender, has said he won't sign Grover Norquist's pledge.
"I’m doing this because in my world, track record counts,” Fiorina said.
Mary Pat Christie resigned her job with the firm as her husband mulls a 2016 bid.
“How can the American people trust her with another position of power?" he asks.
A Fox News poll also shows the Florida senator leading the 2016 Republican field.
“I’m the most experienced, period,” the Ohio Republican governor told a D.C. crowd.
Kevin Cirilli 04/23/15 02:26 PM EDT
"[She's] is going to raise a tremendous amount of money," he said.
The announcement from Peter Schweizer comes as Clinton Cash is under attack.