Concerned Veterans for America, however, has had far more success on the policy front with the Department of Veterans Affairs because it has the ear of the Trump administration, which is in the middle of making a significant shift of veteran health care into the private sector.

Yet the two have also formed a legislative — though never political — bond and are working jointly to persuade Congress to revoke authorizations of military force passed after Sept. 11, which both groups, in spite of many other policy differences, believe have been stretched to justify wars far beyond Congress’s intentions nearly two decades ago.

“We don’t believe in electing veterans simply because they are veterans,” said Nate Anderson, the executive director of Concerned Veterans for America, which spent $6 million in 2018 on races. “We believe in electing leaders who will advance good policy, and it’s great if they happen to be veterans.”

Even as Congress remains unpopular among voters, respect for veterans remains high, and the female veterans found that campaigning as a unified group was useful.

“There was something really powerful about having veterans running,” said Representative Mikie Sherrill, Democrat of New Jersey and a former Navy helicopter pilot. “When you add that we were women,” it was even more so, she said.

Among the new lawmakers, female freshmen formed close relationships during the campaign, and that has carried over into Congress. Part of their bond, besides shared experiences of tough races and their national security backgrounds, was their willingness to work to help one another’s campaigns, which is unusual for insurgent candidates who need to focus on their own races.

“It’s not like half of us were running in really blue districts,” said Representative Elissa Slotkin, Democrat of Michigan, who served at both the C.I.A. and the Pentagon. “We were all doing something that was really difficult. Other party officials, other members of our staff, said, ‘You don’t share your donors’” — advice the group ignored.