Kamala Harris has visited a Minnesota abortion clinic, the first time a US vice-president, or president, has ever visited such a facility, according to the White House.
She toured the Planned Parenthood site with its chief medical officer.
Speaking at the clinic, Ms Harris said she was there because the US was facing a "very serious health crisis".
Her fellow Democrats are seeking to make abortion one of the defining issues of November's US elections.
"Right now, in our country, we are facing a very serious health crisis," Ms Harris said on Thursday at the facility in St Paul.
"And the crisis is affecting many, many people in our country, most of whom are, frankly, silently suffering."
The first woman elected vice-president, Ms Harris has made stops in key swing states such as Michigan, Wisconsin, Georgia and Arizona in recent months as she tries to rally voters on the abortion issue.
Local media reported that both protesters and supporters were outside clinic when she visited, each side numbering about a dozen. Some, though, demonstrate against the clinic on a daily basis.
A co-executive director of the anti-abortion group Minnesota Citizens Concerned for Life said the visit "showed the Biden administration's full-blown devotion to extreme abortion policies".
"Minnesotans don't want to be known for abortion tourism," Cathy Blaeser said in a statement.
Dozens of conservative states imposed restrictions on pregnancy terminations in 2022 after the US Supreme Court overturned a decades-old nationwide right to abortion.
Other liberal states have taken steps to shore up abortion rights. There are no restrictions on abortion at any stage of pregnancy in Minnesota.
Around 12% of voters say abortion is the most important issue for them in the 2024 elections, according to a new survey from health non-profit KFF.
Ms Harris spoke to staff at the Planned Parenthood on Thursday about how abortion restrictions in other states have affected their work in Minnesota.
She commended the clinic for their "true leadership" providing services to women travelling from out of state, adding: "It is only right and fair that people have access to the healthcare they need."
US President Joe Biden, a Democrat, has made abortion a key issue in his re-election campaign, and a central theme of his State of the Union address last week.
He is heading for a rematch against former President Donald Trump, a Republican, in November.
During the State of the Union, Mr Biden took aim at his rival for his appointment of justices that helped cement the Supreme Court's 6-3 conservative majority.
"My predecessor took office determined to see Roe v Wade overturned and he brags about it," he said. "Look at the chaos that has resulted."
When asked in January about creating a court that gave states the right to make abortion illegal, Mr Trump, told Fox News that he's "proud to have done it". Trump has said he supports exceptions in some cases, such as rape.
Many of the people he is considering as a possible running mate - who would replace Ms Harris as vice president in November if he wins the election - are opposed to abortion.
Mr Trump's vice-president when he was in office, Mike Pence, was also strongly opposed to abortion.
