After months of putting up a fight against former Massachusetts Gov. Mitt Romney, former Pennsylvania Sen. Rick Santorum announced Tuesday that he is suspending his campaign for the Republican presidential nomination.

Santorum’s departure clears the path for Romney to take the nomination. Santorum trailed Romney in delegates, 252 to 645. A candidate needs 1,144 to secure the nomination.

“We made a decision over the weekend that while this presidential race for us is over for me, we will suspend our campaign effective today,” Santorum said Tuesday at a press conference in Gettysburg, Penn.

Santorum also cited his three-year-old daughter Isabella’s ailing health as a reason for his leaving the campaign. His daughter, who has a genetic disorder, was hospitalized over the weekend and released.

The announcement comes just a few weeks before the Republican primary in Santorum’s home state of Pennsylvania, where poll numbers were tightening between him and Romney.

“He has proven himself to be an important voice in our party and in the nation,” Romney said in a statement. “We both recognize that what is most important is putting the failures of the last three years behind us and setting America back on the path to prosperity.”

While Santorum did not mention Romney by name in his speech Tuesday, he said he and his supporters would continue to speak out against President Barack Obama and to support the Republican nominee.

“We are not done fighting,” Santorum said.

Julia Azari, an assistant professor of political science at Marquette, said it is up in the air as to what the other candidates will do now that Santorum has left the race.

“It remains to be seen what will happen with (former House Speaker Newt) Gingrich and (Texas Rep. Ron) Paul,” Azari said. “Those two candidates will face less pressure to leave the race than Santorum did, but it depends on how much they win in upcoming contests and how much attention Gingrich draws to himself. Candidates like Ron Paul, who wish to make an ideological point but don’t really enter the main fray of nomination politics, often stay in the race much longer.”

Now that Romney has all but sealed the nomination, both he and Obama can begin gearing up for the general election. Azari said Santorum leaving the race may not have a huge effect on the president at this point.

“Having Santorum in the race helped Obama in two ways: It kept some Republican attention on the internal fight and not on his administration, and it pulled the party to the right, which appeared to hurt its chances with some groups of voters,” she said. “However, I wouldn’t say this affects Obama that much. His main concerns are the economy, the economy and the economy.”