Thousands of abortion-rights opponents are expected to descend on the National Mall on Friday to participate in the 2013 March for Life. 

Organizers expect more than last year's crowd of 400,000 people to attend the event.

"We're expecting a big crowd," March for Life president Jeanne Monahan said, according to NBC Washington."We've seen lots of markers that would show that. Our hotel block sold out a month in advance of what it's ever sold out, and we've had more media requests than ever before, so we expect really record-breaking crowds."

The March for Life is arguably the most high profile anti-abortion protest. It is in recognition of the Supreme Court's Roe v. Wade decision in 1973.

In 2012, House Speaker John BoehnerJohn Andrew BoehnerDems face hard choice for State of the Union response Even some conservatives seem open to return to earmarks Overnight Finance: Trump, lawmakers take key step to immigration deal | Trump urges Congress to bring back earmarks | Tax law poised to create windfall for states | Trump to attend Davos | Dimon walks back bitcoin criticism MORE (R-Ohio) and House Majority Leader Eric CantorEric Ivan CantorEric Cantor: Moore ‘deserves to lose’ If we want to make immigration great again, let's make it bipartisan Top Lobbyists 2017: Hired Guns MORE (R-Va.) addressed the crowd at the event. House leaders are expected to play a smaller role at the 2013 March for Life. Earlier in January, former Sen. Rick Santorum (R-Pa.) announced he would speak at the rally. Santorum, who ran for president last year, has been an outspoken opponent of abortion rights.

"I am looking forward to joining hundreds of thousands of Americans who believe that every life has value and every life must be protected," Santorum said in announcing his participation at the march. "We are a pro-life country, and the March for Life is an important opportunity for us to send a message to our elected officials that they must support policies that foster a culture of life."

The event begins on the National Mall at 12 p.m. The route goes along Constitution Avenue to the Supreme Court building on Capitol Hill.