Rick Santorum, under pressure to bow out of the presidential race, suspended his campaign Tuesday, saying he wants to devote more time to his ailing 3-year-old daughter, Bella.

Her hospitalization over the weekend became “a time for prayer and thought,” Santorum told supporters in Gettysburg, Penn., his wife, Karen, and three of his older children behind him. That caused him and his wife to think about “the role we have as parents in her life,” Santorum said.

The confluence of a sagging campaign, the possibility of losing his home state in two weeks and the continuing illness of his daughter combined to create a moment in which Santorum decided to give up his increasingly long-shot pursuit of Mitt Romney.

Bella, who was born with a rare genetic condition called Trisomy 18, was released from the hospital Monday after a bout with pneumonia. It was not the first time she has been hospitalized during this campaign.

The former senator frequently talks about Bella on the campaign trail, and her condition has no doubt weighed on him. As he has fallen further behind Romney in delegates, it must have weighed on Santorum that he is spending enormous amounts of time on the road, away from his family, in pursuit of an increasingly distant goal.

The candidate said on Tuesday that Bella “is a fighter” and is “doing exceptionally well.” He said many special-needs children came to his events, their families waving signs that said “I’m for Bella’s Dad.”

Santorum has been off the trail since late last week as what began as an Easter break turned into a vigil for Bella, prompting speculation that he might be weighing an end to his campaign.

A suspension enables him to keep raising money to retire his campaign debts.

Santorum’s decision to step aside clears the way for Romney to claim the Republican nomination, probably sooner than if he had stayed in. With Newt Gingrich having drastically scaled back his campaign and conceded that Romney is the likely nominee, his only remaining opponent is Ron Paul, who has not come close to winning a primary.

Despite his decision, Santorum made no mention of Romney or any bow toward party unity now that he is hanging it up.

Romney, for his part, quickly issued a statement, calling Santorum "an able and worthy competitor" and "an important voice in our party."

Santorum spoke wistfully as he rambled about his underfunded, long-shot effort—he wound up winning 11 states—and how his sweater vest became an unlikely symbol of his candidacy. In the end, he said he showed that “your voice could be heard and miracles could happen.”