The most conclusive day of this campaign season began like so many others for the four Republican presidential candidates left: in hotel rooms, fighting colds, with airplane flights and speeches and a long day of work ahead.

Newt Gingrich started with grits and bacon at a chamber of commerce in a Georgia suburb. Rick Santorum pinned an American flag to his suit and flashed a thumbs up at his 648th campaign event. Ron Paul flew from Idaho to North Dakota and promised, once again, to “stick with it.” Mitt Romney settled into his familiar aisle seat in the second row of an MD-90 plane, headed to give another speech in another hotel ballroom at yet another “Victory Rally!”

Here was the latest decisive day in a presidential primary contest that refuses to be decided — in a campaign that has become “a game of survival,” Santorum said.

Even after 11 months, 20 debates, 1,405 rallies and $106 million spent, the four candidates all indicated Tuesday that they foresee a long nomination fight ahead. Super Tuesday might be an event that has historically reshaped presidential races, but this race has been reshaped before and could be reshaped again, the candidates cautioned as voting got underway. Most of them expected to win some delegates Tuesday, and most also expected to lose some. Three had sore throats. Two complained of fatigue. All continued to fill their schedules with events for later in the week, preparing for Super Tuesday to give way to Wednesday and beyond.

They focused less on the results of the day than on the interpretation of those results for the days ahead. Gingrich said the race would become a two-man contest between himself and Romney in the next few weeks. Romney’s advisers said the delegate math stacked up heavily in their candidate’s favor; Santorum indicated that math didn’t concern him, telling a television interviewer that “whether we end up with the most votes or not, we’re winning.”

During 14 appearances in seven states, the Republican candidates framed the election’s biggest day as yet another day typical of this long campaign.

For Gingrich, typical meant an early-morning history lesson in Atlanta, as he talked to a quiet crowd in a suburban office complex about the Wright brothers, Thomas Edison and Henry Ford. He boarded his bus with a slight limp and then flew to Alabama to make another speech, even though Alabamans won’t vote until early next week. His voice was hoarse. His tone was defiant. He said his campaign would continue well past Super Tuesday. He had learned to take the long view on crucial days like this; other so-called decisive moments had made him Romney’s main challenger, then the front-runner, then an also-ran whom some encouraged to drop out of the race.

“For the third time,” he said, “we’re going to come bouncing back.”

Typical for Santorum meant taking the stage at a convention in Washington, D.C., and lecturing without prepared remarks for what his campaign heralded as his latest “Major Foreign Policy Speech.” Gone were the sweater vest and cowboy boots he had worn while campaigning across Ohio a day earlier. He smoothed a wrinkle in his suit and then jabbed his right index finger at the crowd to emphasize his points. “We have a whole lot of primaries going on in the nation, 10 of them, but I wanted to come off the campaign trail and come here,” he said, before walking off the stage and flying right back to the campaign trail for a rally at a high school in Steubenville, Ohio.

Typical for Paul meant traveling to the least typical place — Nampa, Idaho, where some of Romney’s distant cousins stood nearby in support of the Texas congressman and nodded along to his speech. “This is a long-term operation,” Paul told the crowd, referring to the election. “It’s going to be May, I think, before you really start picking or choosing between success or lack of success, or seeing a front-runner.”

Meanwhile, Romney, the front-runner of the moment, spent Tuesday morning in a hotel in Columbus, Ohio, with the Secret Service outside his door. Almost a year into his second bid for the presidency, he had built a campaign that continued to operate with the efficiency and predictability of a machine, but Romney himself had started to wear out. He had been taking DayQuil and NyQuil to get over a cold he caught while shaking hands in a downpour in Florida. He had been going to bed at about 9 p.m. to maximize his sleep, and eating peanut-butter-and-jelly sandwiches in his bus or McDonald’s on the plane, careful to save carbs by removing the middle bun from his Big Macs.

The grind of three hard days of campaigning in the run-up to Super Tuesday had worn him down: ribs in Cincinnati, the “Rocky Top” song in Tennessee, and in Georgia: “Wow, Georgia turns out for pancakes, oh my gosh!” It was the same Kid Rock music at the rallies, the same Gap jeans made to look well-worn, the same applause lines, the same metal bleachers, the same gigantic American flag. It was the same motorcade-to-hotel routine for 60 nights in a row.

Finally, after most of the polls closed on Tuesday, Romney was back home in Massachusetts for the first time since Jan. 6 for his latest “Victory Rally!” He had flown in from Ohio — “Oh boy, we’re headed home!” he said on the plane — voted in his home town of Belmont, and had a private dinner of chicken and mashed potatoes with his wife and sons.

Now he walked to a lectern at a hotel in downtown Boston, where some people waved signs calling him “the next president of the United States.” He turned right to wave. He turned left to wave. “Thank you. Wow,” he said. “What a great night. . . . I’m not going to let you down. I’m going to get this nomination.”

He spoke as the Super Tuesday results continued to roll in — 10 states, more than 400 delegates and a Republican Party still very much divided.

Still four candidates — winners and losers, all.

“Liberty is on a roll,” Paul told an excited crowd in North Dakota.

“We’re going to get a couple more gold medals and a whole passel full of silver medals tonight,” Santorum said in Ohio.

“Lots of bunny rabbits run through, but I’m the tortoise,” Gingrich said in Georgia.

“Tomorrow we wake up and start again,” Romney said in Boston.

It was after 10 p.m. Soon Super Tuesday would turn into Wednesday, the campaigns would roll on, and all four candidates would be back on the road.

Staff writers Philip Rucker, Nia-Malika Henderson and Amy Gardner and research editor Alice Crites contributed to this report.