Former Wyoming Republican Rep. Liz Cheney, who recently endorsed Vice President Kamala Harris’s bid for the White House, said on Sunday that Republicans like Haley who are supporting Trump are abandoning the Constitution and that she could not understand Haley’s decision to support Trump “in any kind of principled way.” In response, Haley said she respected Cheney’s decision to support Harris but that Cheney could not say that deciding to support Trump was “unprincipled.”

“We can either vote based on style, or we can vote on substance,” Haley said on Fox News’s Fox and Friends on Monday. “I’m voting based on substance. I’m looking at the fact we can’t live the next four years like we did the last four years. This is no contest. Harris raised taxes. Trump reduced taxes. Harris wants to stop any energy production. Trump built it up. Harris is weak on national security. Trump was strong on national security. Harris has allowed the border to be infiltrated by 8 million people. Trump was much harder on the border. This is about my family, this is about America, these are about issues.”

Haley added that people can say they dislike Trump but cannot say his policies are worse than Harris’s because “that’s just not a fact.”

Regarding how Trump can expand his support, Haley underscored the importance for the former president to reach out to more centrist voters, such as suburban women and “conservative Democrats.” She added that she is on “standby” and is willing to help Trump on the campaign trail.

The former ambassador also offered her prediction for Tuesday night’s debate, saying both candidates will perform well against each other but that neither can afford to make a mistake.

Cheney’s support for Harris also received criticism from Gov. Sarah Huckabee Sanders (R-AR), who said the former lawmaker is not a conservative nor a Republican for supporting a candidate as “radical” as Harris. She also dismissed Cheney’s endorsement as a “nonfactor” in this election.

Democratic political pundit James Carville, meanwhile, predicted that Cheney’s endorsement, as well as the endorsement from her father, former Vice President Dick Cheney, could push some Republican voters over to support Harris this November. He acknowledged these endorsements might not move a ton of voters but that they have the potential to be “very helpful.”