.- Republican presidential nominee Donald Trump has released a list of 33 prominent conservative Catholic advisers for his campaign, according to reports from Philly.com, a website of The Inquirer and Daily News.

The announcement comes in the midst of a highly contentious election season and at a time when Trump is struggling in the polls among Catholic voters, according to some reports.

Among the released names of advisers are former Republican Sen. Rick Santorum, who ran for president in 2012 and 2016. When he left the race in February, Santorum originally endorsed Sen. Marco Rubio. When Rubio left the race in March, Santorum endorsed Trump, citing the vacant Supreme Court seat as a key reason.

Another key person reported as a new Catholic adviser for Trump is Joseph Cella, founder of the National Catholic Prayer Breakfast who reportedly will be the chief liaison to the Trump campaign for Catholic affairs.

Notably, Cella is a signatory of “An Appeal to Our Fellow Catholics”, an open letter written by George Weigel and Robert P. George during the primaries in March during the primaries and signed by more than 30 Catholic intellectual leaders including Mary Rice Hasson, director of the Catholic Women’s Forum at the Ethics and Public Policy Center, and Thomas Farr, director of the Religious Freedom Project at Georgetown University.

The letter denounced Trump as a man “manifestly unfit to be president of the United States” who has “driven our politics down to new levels of vulgarity.” Citing Trump’s ethnic prejudices, promises to punish the families of terrorists, and his sudden about-face on pro-life issues, among other issues, the signatories pleaded with Catholics not to vote for Trump in the primaries.

The new list of Trump’s Catholic advisers also reportedly includes Tom Monaghan of Michigan, founder of Domino’s Pizza and the Ave Maria University; Marjorie Dannenfelser, president of the anti-abortion group Susan B. Anthony List; Kansas Gov. Sam Brownback; Matt Schlapp, president of the American Conservative Union; former Oklahoma Gov. Frank Keating (R); U.S. Rep. Steve Chabot, Republican of Ohio; Jim Nicholson, former Republican national chairman, secretary of veterans affairs and ambassador to the Vatican; and longtime conservative leader Richard Viguerie.

The election season has thus far been a tumultuous one for Catholics, as leaders such as Archbishop Charles Chaput of Philadelphia have noted.

“Only God knows the human heart, so I presume that both major candidates for the White House this year intend well and have a reasonable level of personal decency behind their public images. But I also believe that each candidate is very bad news for our country, though in different ways,” he said at the University of Notre Dame earlier this month.

“One candidate, in the view of a lot of people, is a belligerent demagogue with an impulse control problem. And the other, also in the view of a lot of people, is a criminal liar, uniquely rich in stale ideas and bad priorities,” he added.

Many Catholic leaders continue to debate whether Catholics can in good conscience vote for Trump, following the voting guidelines laid out by the United States Bishops.

The first debate between Trump and Democratic presidential nominee Hillary Clinton will take place on Monday September 26 at Hofstra University on Long Island in New York.