Getting an accurate count of so large a crowd would be an nearly insurmountable task, but Students for Life of America has put together a 60-second time-lapse video of the March from beginning to end that suggests hundreds of thousands attended the event.
The vice president, accompanied by the second lady Karen Pence, urged the anti-abortion activists to "stand with that love and compassion".
Trump spoke via video to participants at this year's March for Life on the National Mall. He said seeing the "fresh faces" of the young pro-lifers reminded him the pro-life movement "is as vibrant as the values we advocate". But don't listen to them.
"Science is on the side of life", the March for Life 2019 website said. During his speech Friday, Pence said pro-life issues are winning in America. "But we gather here today because we know we still have much work to do".
Steve Daines announced Friday during the March for Life rally that he is forming the first ever pro-life caucus in the United States Senate. "We march to end abortion, with the vision of a world where the beauty, dignity, and uniqueness of every human life are valued and protected". "And because of that, every life must be valued and every life must be protected".More news: Police officer who killed black teenager in Chicago gets almost seven years
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President Trump drew cheers from the crowd as he said that he "will always defend the first right in our Declaration of Independence: the right to life".
However, Pence repeated Trump's promise in his message to the March for Life supporters that he will veto any bill that promotes abortion.
'I think the most unsafe thing we ever did is make this a partisan issue, ' said Destiny Herndon-De La Rosa, 35, president of New Wave Feminists to the Washington Post.
"As passionate activists march for our nation's return to a culture of life, President Trump and the Republican Party remain committed to standing up for the most vulnerable and voiceless Americans", McDaniel added.