Democratic presidential nominee Hillary Clinton campaigns in New Hampshire on Sept. 28. (Melina Mara/The Washington Post)

CHICAGO — The campaign of Democrat Hillary Clinton rolled out another 40 endorsements from prominent Republicans and independents Thursday, the latest play in a bid to lure voters across party lines in her race against Donald Trump.

The list includes three former congressmen, a dozen former high-ranking members of Republican administrations — including a White House ethics lawyer, a director of the Situation Room and an undersecretary of transportation — as well as an array of Capitol Hill staffers, local elected officials and fundraisers for GOP candidates.

The recruits were trumpeted in an afternoon conference call featuring John Podesta, Clinton’s campaign chairman, and several Republicans who’ve joined Together for America, a group launched by Clinton to coordinate GOP outreach.

“In my view, Donald Trump may be the least qualified, least intelligent and least stable person ever nominated by a major party,” said Jim Cicconi, a deputy chief of staff under former president George H.W. Bush.

Cicconi, who was among a previous group of 50 Republican endorsers, added that Monday’s debate highlighted a “pretty clear and pretty stark” choice between Clinton and Trump.

The new endorsements came a day after former five-term Republican senator John W. Warner (Va.) appeared at a news conference to voice his support for Clinton. Warner, a former U.S. Navy secretary a Senate Armed Services Committee chairman, argued that Clinton is far better prepared to lead the nation than his party’s nominee.

The push to highlight GOP endorsers comes as recent polls have showed a tightening race nationally, in part because Trump has made progress in consolidating the support of Republican voters who were initially wary of him.

Some of the Republicans on Thursday’s call argued that many in their party still have qualms about their nominee, and that Monday’s night’s debate has raised new questions about whether he’s prepared for the job.

Claudine Schneider, a former GOP congresswoman from Rhode Island, said Trump has been able to exploit many “vulnerable Republicans” by promising job creation without having a solid plan to back up his words.

“Those that know better,” she said, will wind up voting for Clinton, whom Schneider called “an incredible role model for working with Republicans.”

The other two former Republican members of Congress who stepped forward for Clinton on Thursday were Sherwood L. Boehlert of New York and John J.H. "Joe" Schwarz of Michigan.

Other new names on the list include: Stuart Bernstein, a former ambassador to Denmark under former president George W. Bush; Phil Brady, a former special assistant to then-vice president George H.W. Bush and deputy counsel to former president Ronald Reagan; William A. Pierce, a former deputy assistant secretary for public affairs at the Department of Health and Human Services; Nicholas Rostow, a former special assistant for national security to presidents Reagan and George H.W. Bush; and Roger Wallace, a former deputy undersecretary for international trade at the Commerce Department.

The Clinton campaign call featuring Republican supporters came in advance of a fundraising stop by the candidate in Chicago. Earlier in the day, she campaigned in Des Moines, seeking to shore up support in the battleground state of Iowa, where polls have shown Trump in the lead.