One of two super PACs that helped propel GOP White House hopeful Rick Santorum to second place in the Iowa caucuses is poised to close up shop, underscoring the unpredictable role such groups are playing in this election.

The political action committee, known as Leaders for Families Super PAC Inc., spent just under $107,000 on TV and radio ads and robocalls, public records show. PAC treasurer Charles Hurley acknowledged the sum “is pencil dust” in the big-spending world of presidential politics.

But Hurley took some credit for helping put Santorum within 8 votes of a caucus tie with Mitt Romney, the former Massachusetts governor whose campaign coffers and organization far outstrip Santorum’s. The PAC’s purpose was in part to tout the fact that two prominent Iowa conservatives had endorsed Santorum: Hurley and former GOP gubernatorial candidate Bob Vander Plaats. The two men head a pair of influential conservative advocacy groups in Iowa.

“We got the message out pretty well, I think,” said Hurley, who heads the Iowa Family Policy Center. But Hurley acknowledged that he and Vander Plaats are not well-known outside Iowa and that the PAC is unlikely to shift its focus to other states. “It might happen, but I’m not holding my breath,” he said.

A second pro-Santorum super PAC, the Red, White and Blue Fund, also mounted a modest TV ad campaign for the underdog candidate in the weeks before the caucuses, spending just under $326,000. That PAC’s organizer, Iowa political consultant Nicholas Ryan, could not be reached for comment on the group’s plans.

Super PACs have proliferated throughout the GOP primary, with mixed results. Some have raised and spent millions to promote candidates such as Romney and Texas Gov. Rick Perry; others have grabbed headlines only to fold, rename themselves or switch allegiances within months.

The latest example was Citizens for a Working America, a super PAC that had supported Rep. Michele Bachmann (R-Minn.) but dropped $475,000 on an ad buy for Romney on the eve of the Iowa caucuses. Bachmann has since dropped out of the race. As for Hurley, he said Leaders for Families achieved its goal.

“We really, really wanted to get the word out in Iowa,” he said. “And so, I think we accomplished that.”