Washington (CNN) More than 50 former US national security officials and lawmakers endorsed Gina Haspel, President Donald Trump's controversial pick to head the CIA, in a letter sent Monday to the Senate Intelligence Committee.

Former directors of the CIA and national intelligence, secretaries of state and lawmakers who have chaired the Senate and House intelligence committees make up the list of signatories. The top intelligence officials include former CIA Directors John Brennan, Leon Panetta, Jose Rodriguez, George Tenet, Michael Hayden and former President Barack Obama's Director of National Intelligence James Clapper.

"Ms. Haspel's qualifications to become CIA Director match or exceed those of most candidates put forward in the Agency's 70-year history," they write. "She has spent more than 30 years of her life quietly serving America and the CIA, routinely stepping up to handle some of the most demanding assignments around the globe."

Officials within the Trump administration have been concerned that Haspel, who is currently the agency's deputy director, may have trouble being confirmed for the director position due to her role in the CIA's past controversial interrogation and detention program, including her oversight of a CIA "black site" in Thailand in 2002.

The letter does not address these issues but says Haspel is a leader who "has what it takes to make tough calls in times of crisis."

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