After endorsing Kamala Harris on X Sunday, former Republican Sen. Jeff Flake of Arizona praised the vice president's grasp of foreign policy and her proposal for tougher border restrictions on ABC News' "This Week."
With 37 days until Election Day, Flake said he made his endorsement now since he couldn't participate in political activities in his role as ambassador to Turkey, which he stepped down from on Sept. 1.
"I think Republicans believe in the rule of law in particular, and it's difficult to support a candidate who, having lost an election, tries to use the powers of the presidency to overturn that election," Flake told ABC "This Week" anchor Martha Raddatz. "That is anything but respect for the rule of law."He said that other conservative Republicans feel similarly.
In his endorsement, Flake wrote that he believes Harris will unite the country and "respect the will of voters." He also discussed his endorsement in an interview with the Arizona Republic.
The former congressman and senator joins other prominent Republicans who have endorsed Harris, including former Vice President Dick Cheney and his daughter, former Rep. Liz Cheney of Wyoming.
Flake is one of a handful of Republicans who have served in President Joe Biden's administration, along with Cindy McCain, the widow of former Sen. John McCain of Arizona. Since leaving the Senate in 2019, Flake has been an outspoken critic of former President Donald Trump and urged Republicans to "move away from Trump-ism."
Flake also endorsed Biden in 2020 on the first day of the Republican National Convention along with dozens of former GOP members of Congress.
He said that Harris "ought to court all voters," particularly moderate and conservative Republicans.
Asked about his interactions with Harris during his time as an ambassador, Flake said that she is ready to serve as commander in chief.
"We have to support and work with our allies," Flake said. "And she understands that."
He pointed to Harris' speech at the Munich Security Conference and each candidate's approach to foreign policy during the ABC presidential debate.
"It was really stark watching the debate the other day and hearing the former president not be able to even cheer for Ukraine," said Flake. "That's a big issue for me."
Raddatz pressed Flake on whether his endorsement would make inroads with voters in Arizona who are a part of the Church of Jesus Christ of Latter Day Saints, of which he is a member. Sen. Mitt Romney, R-Utah., another high-profile Mormon Republican opposed to Trump, has not endorsed Harris.
Flake demurred, responding that "I can only speak for myself and where I am."
Raddatz asked Flake about his thoughts on one of the vice president's biggest vulnerabilities after her visit to the U.S.-Mexico border on Friday, her first in three years. A recent ABC News/Ipsos poll found that voters thought Trump was better suited to handle the border over Harris by 10 points.
Flake said that he was glad to see Harris visit the border and propose stricter asylum restrictions. He pointed to her work as a prosecutor and attorney general, saying, "She knows what it takes." Harris' campaign is looking to gain ground on an issue of high importance to voters.
While in Congress, Flake backed a bipartisan immigration proposal that failed to pass. When pressed by Raddatz on the Biden-Harris administration's handling of the southern border, Flake said there needs to be stricter asylum policies.
He applauded Harris for saying she would sign the immigration bill that failed in the Senate after Republican opposition led by Trump cratered the legislation.
"She knows how to work on a bipartisan basis, and if we do immigration reform that endures, it's going to have to be bipartisan," said Flake.