(CNN) As Joe Biden prepared to tell a crowd that he'd changed his mind and now supported allowing federal funds to pay for abortions, he offered a disclaimer: He still didn't think he'd been wrong before.

"I make no apologies for my last position and I make no apologies for what I'm about to say," the former vice president told those gathered for a Democratic National Committee gala in Atlanta on Thursday night.

Biden's remarks sought to avoid the appearance of flip-flopping on a key issue out of political expediency. Still, pressure from both inside and outside Biden's campaign, including a direct appeal from a prominent supporter, actress and activist Alyssa Milano, led Biden to conclude he had to reconsider his position, according to campaign officials with direct knowledge of internal discussions around the matter.

The tumultuous 38 hours offered the first window into how the man vying to lead Democrats into the future will wrestle with a political past that is now out of step with the party on some major issues.

It also raised questions about how Biden will handle clashes with his Democratic opponents on issues such as his role in crafting the 1994 crime bill and his vote to authorize the war in Iraq.

"It takes courage to admit when you're wrong, especially when those decisions affect millions of people," Massachusetts Rep. Seth Moulton tweeted Friday. "Now do the Iraq War."

Biden long supported the Hyde Amendment, which prohibits federal dollars from paying for abortions except in cases of rape, incest and to save the life of the mother. However, when an ACLU volunteer pressed him about it after an event in South Carolina in May, Biden told the woman -- twice -- that "it can't stay." Video of the exchange was posted on Twitter.

On Wednesday morning, Biden's campaign backtracked, saying he'd misunderstood the woman's questions and that Biden still supports the Hyde Amendment. That put him at odds with women's rights groups, the Democratic Party's platform and all of his leading opponents for the 2020 nomination.

Biden then announced Thursday night that he'd changed his mind because largely Republican-led states have enacted strict new abortion laws in recent months.

"If I believe health care is a right as I do, I can no longer support an amendment that makes that right dependent on someone's zip code," he said.

Biden campaign officials insisted his change of view hadn't come as a result of the political backlash he faced. If so, they argued, why hasn't he declared support for "Medicare for All" or apologized for the crime bill?

Two officials directly involved with the decision say Biden heard the arguments and changed his position on the merits. They said this does not signal the beginning of an apology tour. He does not believe he has to apologize for the crime bill, for example, but he does acknowledge a need to explain it better and accept that it had negative consequences for a generation.

"He's put together a diverse set of voices around him that are reflective of the country and that means where the country is today and he heard that," another source said.

Biden's campaign knew his support for the Hyde Amendment would spark outrage. It was the topic of intense meetings both before and after NBC first reported his continued support for the Hyde Amendment on Wednesday.

Several people within the campaign on multiple occasions pressed him on why it's important to repeal Hyde, pointing out "why that's problematic from a point of view of low income women and women of color and the impact that had and that it's different now with threats to abortion and Roe," one source familiar with the matter said.

Aware of the criticism he was certain to face, Biden's camp gave advance notice to Planned Parenthood and other progressive organizations. Those groups had been pleased to see the video posted on Twitter in May in which Biden told an ACLU volunteer he opposed the Hyde Amendment. Their leaders were surprised that a reversal was coming and pushed back hard, at first privately, and then publicly starting Wednesday morning.

Biden's Democratic opponents piled on, marking the first time the full 2020 field had ganged up on the former vice president.

"His team gave him a very unvarnished view of what would happen," one source familiar with the matter said. "I think he needed to kind of see that and also feel it and also hear from his core supporters, and he's very open to hearing from his people."

Senior adviser Symone Sanders and other aides made a forceful case directly to Biden on Thursday in Atlanta that ultimately led to him changing his long-held position on the Hyde Amendment, people familiar with the matter say.

They argued that poor women and women of color were deeply impacted by this, people familiar with the matter say, which was a point of view Biden ultimately came around to. Of course, it also came in the wake of extraordinary pressure from abortion rights groups who said his position was untenable.

"We made the argument about access to health care. It was a thoughtful, logical evolution, not a flip-flop for political reasons," said a person familiar with the matter who spoke on condition of anonymity to discuss internal deliberations.

The former vice president and top campaign advisers heard from several prominent supporters in the last two days that his stance was problematic, including from actress and activist Milano, who made the case to campaign manager Greg Schultz and to Biden directly.

After he announced his new position Thursday evening Atlanta, Milano met with Biden backstage, hugged him and thanked him for listening, a person familiar with the encounter said.

What neither Biden nor his aides have explained is what changed -- aside from public and private pressure -- between Wednesday morning and Thursday night.

Pressed on Biden's thought process, deputy campaign manager Kate Bedingfield said on CNN Friday that "this was a tough personal decision for him, but the substantive explanation is that the moment we're in now is a dramatically different one."

"He looked at the crisis that we're facing on choice in this country, and he made that decision," she said. "That's authentic to who he is. He's somebody who says what he believes."