The University of Notre Dame conferred an honorary law degree on President Obama Sunday. The honor was met with cheers and applause inside the commencement ceremonies, even as protesters descended on and around the campus in opposition to the president's visit. 

More than 100 protesters demonstrated on Notre Dame's campus Sunday ahead of Obama's commencement address, as the national debate over abortion and embryonic stem cell research played out in an ultra-concentrated setting. 

Demonstrators showed up in their largest numbers yet as Obama arrived in South Bend, Ind. They largely gathered outside the gates of the university, but organizers said about 20 are inside and plan to demonstrate during the commencement ceremonies. Those protesters plan to go limp if they are asked to leave and force authorities to physically remove them, organizers said. 

With Obama's address set for mid-afternoon, the demonstrations Sunday took on several forms. Many people prayed while others wielded graphic signs. Obama is expected to address the controversy at length but not make it the focus of his speech. 

About 300 people had arrived at the university's grotto Sunday afternoon for a prayer vigil, an event designed as an alternative to commencement ceremonies. The group included at least 25 graduating seniors who were boycotting their own graduation. 

Several hundred people also attended an outdoor Sunday mass led by Father Kevin Russeau on the university's South Quad. 

"What has been inspiring to me ... is that our student body has come to the Lord for guidance" for the proper response to the controversy surrounding Obama's visit, Russeau said. 

Cornelius Griggs, a graduate student of physics at Notre Dame who attended, said he was "impressed" by the large turnout. 

"I'm surprised this many people came out," said Griggs, 25. "It seems this issue is important to a lot of people." 

He said he opposes Obama's visit because "his policies are opposed to the culture of life and therefore our Catholic values." 

Other protesters decorated their mortarboards with the image of a cross and two baby feet. 

However, the jagged tone of some of the protests was riling members of ND Response, a group that had organized ahead of time in opposition to Obama's visit. 

ND Response spokesman John Daly said he took issue with protesters who were wielding graphic pictures of aborted fetuses outside the gates. 

"That's not Notre Dame," Daly told FOXNews.com. "You teach through winning over the mind. We don't feel that those images will do anything constructive." 

Protesters also held signs like "Obama = Abortion" and "Shame on Notre Dame." Law enforcement continued to make arrests Sunday, with 36 reported by the local sheriff's office. Among those arrested was Norma McCorvey -- the plaintiff in the landmark Roe v. Wade case who now opposes abortion. 

Most students are not protesting Obama's visit or the university's decision to grant him an honorary degree. 

Supporters of his visit say the university is not in any way conveying support for Obama's abortion positions by awarding him a degree, and questioned the merit in demonstrating against the president. 

"I don't know how this is going to solve the issue of abortion," university senior Michael Angulo told FOX News. He said people like Alan Keyes, a former presidential candidate, were using the Notre Dame campus to make political statements. 

But opponents say the university is treading on a key tenet of Catholic teaching. 

Another Mass attendee, James Germalic, provided FOXNews.com a letter he hopes will reach Obama. 

"Your appearance at Notre Dame is magnified a million times, for a Catholic university is going to honor you and then you're going to do the unthinkable -- put in a pro-abortion judge, dooming the pro-life movement, the Catholic church, the nation and condemning yourself to hell," Germalic wrote. "Don't worry about the politicians in Washington, they have brought this country to ruin. Worry about us, we are Catholics, we are America. It's your last chance to listen to the voice of the pro-life." 

FOXNews.com's Joshua Rhett Miller and FOX News' Griff Jenkins contributed to this report.