Correction: The article about a march to the Supreme Court in protest of the 1973 Roe v. Wade ruling misspelled the name of the high school in McKeesport, Pa., where one of the protesters, Jan Fox, is a teacher. It is Serra Catholic High School. This version has been corrected.

Abortion opponents from across the country marched on the Supreme Court on Friday to protest the landmark ruling that established a constitutional right to abortion, and they cheered on speakers who vowed to work for more restrictions.

Though some in the crowd were veterans of previous marches held annually since Roe v. Wade was decided in 1973, the majority seemed to be teenagers and young adults, many of whom carried signs identifying themselves as part of a “pro-life generation.”

Buses from across the country, mostly chartered by Catholic schools and organizations, brought groups of people to the Mall for a pre-march rally in which politicians, religious leaders and activists decried the 55 million abortions they said had been performed since the Roe v. Wade decision.

The archbishop of Boston, Cardinal Sean O’Malley, read a message posted early Friday by Pope Benedict XVI from his personal Twitter account: “I join all those marching for life from afar, and pray that political leaders will protect the unborn and promote a culture of life.”

House Speaker John A. Boehner (R-Ohio) appeared on a giant video screen and vowed to work for passage of a bill banning taxpayer funding for abortions. Rep. Diane Black (R-Tenn.) told the crowd that she would fight for a bill she has introduced that would prohibit family planning grants from going to groups that provide abortions, such as Planned Parenthood.

Rep. Christopher H. Smith (R-N.J.), chairman of the Congressional Pro-Life Caucus, called President Obama, who has stated his commitment to protecting abortion as a constitutional right, the “abortion president.”

“Know this, Mr. President,” Smith said to loud cheers from the crowd of protesters. “We will never quit.”

The March for Life is typically held on Jan. 22, the actual anniversary of Roe v. Wade. This year, it was delayed until Friday to allow for cleanup after Monday’s presidential inauguration and make it easier to travel to the District.

Despite a bitter, arctic cold that descended over the region, Friday’s crowd was large. Police no longer estimate crowd size, so it is difficult to judge how many people attended.

The march permit was for 50,000 people, though organizers said the attendance was several times that number. People at the rally were concentrated on the Mall between Seventh and 12th Streets, and the march up Constitution Avenue stretched for at least five blocks.

The most commonly carried posters simply said, “Defend Life,” or showed a black-and-white photograph of a newborn infant, plump and healthy-looking. Posters with graphic images of aborted fetuses were rare.

Jeanne Monahan, the new head of the March for Life, said the movement is making progress in changing laws and attitudes. She noted about 200 antiabortion measures introduced in state legislatures, and said Americans are becoming growing more “pro-life.”

“Pro-life is the new normal in the United States,” she told the crowd.

Many who participated came in groups, identifiable by the banners they carried or the matching scarves they wore. Chartered buses dropped off people several blocks away, and they approached the Mall on foot, often carrying placards, crosses and flags bearing the name of the college, high school or diocese they represented.

A group of 24 eighth-graders from Spiritus Sanctus Academy in Plymouth, Mich., spent the past year raising $3,000 for the trip through fish fries, rummage sales, can returns, paper recycling and poinsettia sales. Going to the march has been an eighth-grade tradition at the school for several years, said Sister Maria Guadalupe, 37, who was chaperoning the class.

“From the time they’re in kindergarten, we teach them about the dignity of the human person,” she said.

“It’s kind of, for them, an introduction into what we hope for them,” she added. “Standing up as citizens, standing up as believers — these are our rights as Americans; this is what we do as Catholics.”

Jan Fox, who accompanied 37 students from Serra Catholic High School in McKeesport, Pa., said she had attended the march virtually every year since she was brought to one when she was an eighth-grader in 1998.

“As a committed Catholic, we should always be optimistic,” she said, expressing her hope that abortion will be banned again. “Things can change.”

Many young protesters carried placards saying, “Defund Planned Parenthood,” on one side, and on the other side, “I am the Pro-Life Generation.”

Veronica Estigoy, 16, a junior who is treasurer of the pro-life club at Ladywood High School, a Catholic girls’ school in Livonia, Mich., said more teenagers probably fit that description than are willing to admit it.

“I still feel like we’re struggling,” she said of the antiabortion movement among teenagers. Too many teens consider abortion “a get out of jail card,” she said. “But I have the feeling something’s going to change, there are going to be steps taken so we’re not coming back here in another 40 years.”

Cathy Flowers, who came to the Mall on a bus with about 50 fellow members of St. Michael’s Roman Catholic Church in Annandale, said there was something auspicious about Roe v. Wade being 40 years old.

“Forty is a religious number,” she said.

“The Israelites spent 40 years in the desert. There were the 40 days and nights of rain for Noah. So I’m hoping maybe it will start getting better.”