"The party was shaken by that," Scott Reed said. "We're all worried," he added.
McCarthy, an Arizona businessman, hopes to win the Senate seat formerly occupied by Sen. John McCain in the first general election since the longtime senator's death in 2018.
The first-term lawmaker told Newsweek that after weeks of studying the evidence, she's determined the accusations levied against the four-star general are false.
Outgoing GOP congresswoman is chosen by the state's governor to serve the remaining two years of John McCain's term.
Voters elected the country's first Muslim and Native American women to Congress, in addition to a number of other firsts.
"It was OK for Americans to join the Taliban to fight against us," McSally said.
"Sorry, [Donald Trump]. I made no endorsement in this race," Jeff Flake responded on Twitter.
Martha McSally is leading the Arizona GOP Senate primary, but she has had to shift her campaign to respond to recent attacks from her more conservative primary opponents.
Under pressure from her hardline anti-immigrant opponents, a GOP candidate for Senate from Arizona appears to have removed a video of her supporting DACA.
"I told Washington Republicans to grow a pair of ovaries and get the job done," she says in the video.