HARRISBURG, Pa.—Rick Santorum said Monday that he hopes to say soon how he will continue to press for conservatism in politics, although he didn't give details and didn't reveal whether he'd eventually endorse all-but-certain GOP presidential nominee Mitt Romney.

Santorum and his wife, Karen, spoke on a half-hour conference call to thank supporters, less than a week after he dropped out of the GOP presidential race. But he insisted Monday, as he did last week, that he will continue what he views as a divine calling.

"Let me assure you, we're not backing away one bit from our efforts," Santorum said.

Santorum also insisted that money woes were only a small piece of the story behind his decision to drop out.

He didn't name names, but said efforts to win backing from other conservatives in the race failed, as did an effort to persuade Texas' Republicans to award delegates on a winner-takes-all basis. That left him without a clear path to success, and it was too much to ask supporters to keep helping him if he didn't have a strategy to win.

He also said his 3-year-old daughter's hospitalization had heaped a lot of stress and strain on the family.