WASHINGTON — From obscure former senator driving a pickup truck across Iowa, Rick Santorum made a surprising — he calls it miraculous — leap to become the most formidable threat to Mitt Romney's march to the Republican nomination. His shoestring campaign, which ended Tuesday, was a constant reminder of Romney's trouble connecting with the party's conservative core.
Santorum's presence in the race pushed to the fore polarizing social issues, such as abortion, access to birth control, and gays in the military, that many in the party preferred not to delve into as the GOP prepared to court independent voters in the general election campaign against President Barack Obama. Although he accused the media of unfairly focusing on that part of his broader campaign, Santorum was unapologetic about taking on such issues.
"We did focus a lot, yes, on the families and on the dignity of human life and on the moral enterprise that is America," he said Tuesday in Gettysburg, Pa., as he announced his decision to suspend his campaign.
He added: "We were winning in a very different way because we were touching hearts. We were raising issues that, well, frankly, a lot of people didn't want to have raised."
As it became obvious Santorum could not triumph in the primaries and caucuses, he began talking of an unorthodox strategy of stealing the nomination away from a weakened Romney at a divided Republican National Convention. Santorum argued that the delegates would embrace him as the true conservative in the race, even though most are being sent to the convention by voters who chose Romney.
Many Republicans bent on showing unity against Obama considered such a strategy disastrous and began calling for the party to unify around Romney as the presumptive nominee.
While Santorum avoided mentioning Romney on Tuesday, he pledged to stay in the fight to defeat Obama, which presumably means embracing the party's nominee at some point. In a recent interview, Santorum even said he was open to the possibility of becoming Romney's running mate.
He seems an unlikely choice for Romney, given that just last month he was calling the former Massachusetts governor "the worst Republican in the country" to challenge Obama.
Santorum likes to compare himself to President Ronald Reagan, a fellow conservative who happens to have lost his own first bid for the party's nomination before winning in a landslide four years later. The comparison suggests Santorum might expect better chances for himself in 2016, should Obama win re-election.
No matter what, Santorum has made himself a national name and gained influence over his party's agenda.
His withdrawal came after he had fallen hopelessly behind Romney in the race for GOP delegates. And he risked an embarrassing loss in his home state of Pennsylvania if he stuck around for its April 24 primary. Polls indicated his once strong lead slipping away in Pennsylvania, which ousted Santorum from the Senate in a rout in 2006. Many voters there still remember him unfavorably.
Santorum said he made the decision to leave the race with his family over the weekend as his daughter Bella, who suffers from a rare and serious genetic condition, was hospitalized.
One Pennsylvania supporter, Chad Collie, said Santorum's withdrawal left him "speechless."
Collie, owner of a plaster and drywall business, had brought his wife and two children, ages 3 and 5, to what he expected to be a Gettysburg campaign event for the "truly genuine conservative" he planned to support in the state's GOP primary. Would he be willing to vote for Romney instead? "We'll see," said Collie, who views Romney as about the same as Obama. "I'm not opposed to a third party."
Early on, Santorum wrestled with competing images: He was the sweater vest-wearing, smiling underdog, a devoted father of seven taking on the Republican establishment and a multimillionaire front-runner. But he could also come across as a stern moralizer, worried that birth control was harming the nation and government-funded preschools were indoctrinating America's children into liberalism. He seemed to think working mothers would do better to quit their jobs and home school their children, as his wife, Karen, did.
He called Obama "a snob" for wanting all Americans to have the opportunity to go to college. And he said fellow Roman Catholic John F. Kennedy's famous 1960 speech about the separation of church and state made him want to "throw up."
Republicans questioned whether Santorum could appeal to party moderates and independents — and female voters — if he were the party's nominee.
Santorum pointed to his four years in the House and 12 as a senator and argued that he had a stronger command of foreign and military affairs and the national economy than his opponents.
He reveled in his underdog status, reminding supporters that his campaign lacked the money and slickness of Romney's effort and that he spoke from the heart rather than prepared notes. At times, though, he appeared to talk himself into unnecessary controversies, as when he said the economy wasn't the race's top issue and that unemployment didn't concern him as much as the federal government's threat against individual freedom.
Santorum did things the hard way, with relatively little money and scant campaign organization. At times on the campaign trail he bunked in a supporter's guest room.
Even his breakthrough win in the race's first contest, the Iowa caucuses, was bumpy.
Santorum, barely noticed amid a large, colorful Republican field, eked out a surprising victory over his better-funded opponents after doggedly holding 385 town hall meetings across the state. Initially Romney was declared the winner — by just eight votes — and Santorum was relegated to second place. But a few weeks later, the Iowa GOP sheepishly acknowledged errors in the balloting and declared Santorum the winner by 34 votes.
The delayed victory and a thinning field did little to help him in the next four states, where he typically finished in third or fourth place. Fundraising remained a problem, and Santorum was at times overwhelmed by the often negative TV ads supporting Romney.
Santorum's big night came Feb. 7, when he won all three of the states voting: caucuses in Colorado and Minnesota and a nonbinding primary in Missouri
Santorum and Romney tussled in a series of debates. Santorum tried to cast Romney as unable to challenge Obama on his health care law because of his support of a similar health care policy in Massachusetts. Yet Santorum stumbled — he was even booed — when he acknowledged during an Arizona debate that in Congress he had supported the No Child Left Behind law and other legislation he disagreed with because he had to support the overall Republican effort and "take one for the team."
As other candidates peaked and fell to the wayside, Santorum soldiered on to become the only realistic threat to Romney's ascension. Despite winning Super Tuesday contests in North Dakota, Oklahoma and Tennessee and later balloting in Kansas, Alabama, Mississippi and Louisiana, he kept falling further behind Romney in the delegate count. Santorum said he won those 11 states "against all odds."
"Miracle after miracle," he said Tuesday. "This race was as improbable as any race that you will ever see for president."
Associated Press writer Marc Levy in Gettysburg, Pa., contributed to this report.