For the first time in years, abortion opponents will have all the political momentum when they hold their annual rally on the National Mall.
Mr Pence is a longtime hero of the anti-abortion movement and as governor of IN, he signed what were seen as some of the nation's strictest abortion laws.
This week he reinstated the Mexico City policy, which cuts off us aid to worldwide health groups that promote or provide abortions, following in the footsteps of other Republican presidents.
Pence called it "the best day I've ever seen for the March for Life in more ways than one".
President Trump's White House counselor Kellyanne Conway told an enthusiastic crowd of antiabortion advocates that this is their time to be heard, calling it a "new day, a new dawn for life". "As they sit there, they stand here with you".
"We have people who could be open to a message that everyone is a person, and that unborn children deserve rights and respect and protection", said Allard.
"I do feel very positive that things are happening since Trump and the Republicans have control of Congress", Ann, a protester from IL told DW.
A Christian rock band warmed up the crowd for Pence, leading people in hand-clapping at the rally within sight of the White House.
Jeanne Mancini, president of the March for Life, suggested many voters chose Mr Trump mainly because he had pledged to appoint a Supreme Court justice who shared their views on abortion, even if they disagreed with him on other issues.
"It all for me begins with cherishing the dignity, the worth, the value of every human life", Pence said on the debate stage.
Since the Supreme Court ruled abortion legal in the 1973 Roe v. Wade decision, marchers have descended upon Washington to protest the ruling. Pew Research Center polls have found that 59% of USA adults today support the legality of abortion in general, and 69% want the Supreme Court to uphold Roe - numbers that have both risen over time.
At the rally, the crowd, including young people, cheered as speakers told of plans to defund the reproductive health organisation, Planned Parenthood, through Congress. Critics and healthcare providers have said this does not reduce abortions, but makes them unsafe and puts women's lives at risk.
The rally comes as the number of U.S. abortions has fallen to a record low.
"Forty-four years ago our Supreme Court turned away from the first of these timeless ideas", he said. Pence says it's the first of many moves toward a more pro-life America.