Debate moderators David Muir and Martha Raddatz speak to the audience before the Democratic U.S. presidential candidates debate at St. Anselm College in Manchester, New Hampshire, Dec. 19, 2015. Reuters

The Republican U.S. presidential candidates are set to square off in a debate Saturday at St. Anselm College in Manchester, New Hampshire, where they’ll be grilled by ABC News journalists David Muir, the anchor of “ABC World News Tonight with David Muir” and Martha Raddatz, the co-anchor of “This Week with George Stephanopoulos.” The GOP candidates will also answer questions by Josh McElveen, the political director of WMUR-TV in Manchester, and Mary Katharine Ham, a contributor to Fox News.

As co-moderator, Muir will bring to bear his experience as a former global correspondent at ABC News as well as the anchor of “ABC World News Tonight.” He has reported from the White House, on the Syrian border and in Cuba, Egypt, Haiti and elsewhere, according to KERO-TV in Bakersfield, California. With Raddatz, he co-moderated the Democratic presidential candidates debate at St. Anselm College in December.

Raddatz served as a White House correspondent during the Bush administration. She also has reported from all corners of the globe, according to her ABC News biography, which noted, “Her coverage at the State Department after the attacks of September 11 [2001] was recognized, along with that of other ABC News recipients, with a Peabody Award as well as an Emmy Award.”

Raddatz was praised by pundits after the debate in December. “Raddatz’s strong performance also continued a trend in which moderators who are primarily reporters rather than anchors — such as CBS’ John Dickerson — showed how their chops could outshine the full-time anchors whose easy professional manner tended to blur rather than accentuate the differences between the candidates,” Politico’s Hadas Gold wrote.

Muir paled in comparison with Raddatz, according to Gold. “In this debate, the anchor in question was David Muir, the youthful star of ‘World News Tonight’ and a novice to debate moderating,” Gold wrote. “He was a smooth questioner, but lacked Raddatz’s sharp eye for evasions and inconsistencies. At many points, he was talked over by the candidates.”

Ham, who is considered a conservative journalist, was a recent addition to the debate sponsored by ABC News, Independent Journal and WMUR. Her role in the debate was announced Thursday. “Very proud that [she] will be on stage to ensure conservatives have a voice,” Republican National Committee communications director Sean Spicer said on Twitter.

McElveen is a well-known personality in New Hampshire, where he covered the 2012 presidential election, landing interviews with President Barack Obama.

The debate is set to start on ABC Saturday at 8 p.m. EST.