A day after officially announcing his second White House run, former Pennsylvania Sen. Rick Santorum ended his week-long silence on allegations that “19 Kids and Counting” star Josh Duggar molested underaged girls when he was a teenager.

“I was sickened by it. I was just sickened by it,” Santorum, a Christian conservative whom the Duggars endorsed in 2012, said in an interview that aired Thursday on ABC News’ “Good Morning America.”

“I pray for those girls in particular,” Santorum added.

The comments stand in stark contrast to a robust defense of the Duggars that former Arkansas Gov. Mike Huckabee posted on Facebook last week, shortly after In Touch magazine published a police report listing the allegations. Until now, Huckabee was the only Republican White House hopeful to have addressed the matter, despite the fact that nearly every member of the emerging GOP presidential field can be found smiling with the now-27-year-old Josh Duggar on his Twitter profile.

Duggar has since apologized for acting “inexcusably,” while his parents have acknowledged “some very bad mistakes” made by their oldest son. But aside from Huckabee and, now, Santorum, the GOP pack has largely stayed silent on the apparently radioactive Duggars, once considered a valuable line to many Republican Party evangelicals.

That may be a collective attempt to elevate presidential politics above the tabloid frenzy so often surrounding reality TV stars’ every action – especially if the action in question is more than a decade old. Or it may be more of a strategic silence, borne out of a concern that in a primary field as crowded as this one, every vote – particularly those of the older, whiter, more religious base – makes a difference.

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“It’s difficult for a Republican running for president because the narrative that [Duggar] did a terrible thing who has repented and changed his life is central to any sort of Christian faith, and particularly central to the evangelical view of the world,” said Henry Olsen, senior fellow with the Ethics and Public Policy Center, a conservative think tank.

“In the absence of any evidence, it’s very difficult for candidates to make a statement because they’re either confirming or denying that basic narrative of sin and repentance,” Olsen told msnbc. “If you’re denying it without any evidence, you’re clearly taking on the family and running into issues with Christian conservatives. If you’re affirming the narrative, you’re clearly going to have difficulties with voters more on the secular side. Given that most of these candidates have no personal ties [to the Duggars]… it’s much better to just be radio silent.”

Clearly, that message has gotten through. Of the long list of prominent Republicans who have, at the very least, mugged for a photo with the oldest Duggar kid, former Arkansas Gov. Mike Huckabee was – until Thursday – the only presidential hopeful to have said anything about the allegations.

“Josh’s actions when he was an underage teen are as he described them himself, ‘inexcusable,’ but that doesn’t mean ‘unforgivable,’” Huckabee said in a Facebook post last week.

As Arkansas natives, the deeply religious Duggars have been longtime supporters of Huckabee, who is also a former Baptist pastor. Jim Bob and Michelle Duggar campaigned for Huckabee during his 2008 presidential bid – back when they were parents to only 17 kids. They even “begged” Huckabee to run again in 2012, but he refused. After Huckabee officially launched his 2016 bid earlier this month, it only took a day for the Duggars’ endorsements to pop up on the governor’s campaign website.

Given that closeness, it’s perhaps not surprising that Huckabee came to the Duggars’ aid last week. But Huckabee is far from the only politician with ties to the family. In 2012, the Duggars threw their weight behind former Pennsylvania Sen. Rick Santorum, who – like Huckabee in 2008 – won the Iowa caucuses with broad support from evangelicals. In 2014, several of the Duggars traveled to Kansas to help two Republican incumbents – Gov. Sam Brownback and Sen. Pat Roberts – eke out victories in tough reelection fights. The famous family even cozied up to former President Bill Clinton, a Democrat and fellow Arkansan, during back-to-back appearances on “The TODAY Show” in 2011.

Spokesmen for both Brownback and Roberts provided statements to msnbc condemning Josh Duggar.

“Senator Roberts thinks it’s tragic and as the grandfather of five, his thoughts are with the young victims of the abuse,” said Sarah Little, Roberts’ communications director, via email. “He obviously had no knowledge of this and finds it completely deplorable.”

“What Josh Duggar did was wrong. Period,” Brownback said in a brief statement provided by Eileen Hawley, the governor’s communications director.

But a spokesman for Santorum, who officially announced his second White House run on Wednesday, did not respond to msnbc’s repeated requests for comment. Other likely or already-declared Republican presidential candidates – a group which includes Wisconsin Gov. Scott Walker, Florida Gov. Jeb Bush, Texas Sen. Ted Cruz, Louisiana Gov. Bobby Jindal, and Kentucky Sen. Rand Paul, among others – were similarly silent on the matter, though each hopeful has met with Duggar in the last few months.

“I think if you’re a candidate, you’d argue that it’s not a relevant question,” said Kedron Bardwell, an associate professor of political science at Simpson College in Indianola, Iowa. “In an era of ISIS, they have bigger fish to fry than Josh Duggar.”

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Be that as it may, it’s hard to imagine that these GOP hopefuls saw no political value in looking chummy with the Duggars when they were one of America’s most popular and powerful conservative families. Once scandal hit, though, then what? Republican candidates found themselves too busy to comment on just another “reality TV family” – a category to which the Duggars were suddenly relegated? If that’s what’s going on, the maneuver seems deeply political to its core.

Bob Vander Plaats, an influential social conservative activist in Iowa and head of The Family Leader, believes the relative silence among the GOP field has more to do with sensitivity toward the family than politics, although even that argument seems laced with a concern for the evangelical base.

“I just don’t think it’s time for criticism,” Vander Plaats told msnbc. “I don’t think there’s anybody – candidate or non-candidate, Christian or non-Christian – that says, ‘We support what happened at age 14 with Josh Duggar.’”

“It’s time for the Christian community to come around Josh Duggar and his family in prayer,” he continued. “What this reminds us of as Christians is that we’re all fallen and we’re all in need of a savior.”

Editor’s note: This story has been updated to reflect an interview with former Pennsylvania Sen. Rick Santorum that aired Thursday on ABC News’ “Good Morning America.”