Democrats have made health care a moral issue, based on a compelling argument, passionately held, that everyone deserves access to care by virtue of being human.

That’s one context to keep in mind as the party’s powerful pro-choice contingent attempts to transform a morally contentious issue, abortion, into a health-care issue that – unlike the party’s approach to health care generally – is stripped of moral content.

Last week, Naral Pro-Choice America President Ilyse Hogue condemned the Democratic National Committee’s support for Heath Mello, a candidate for mayor of Omaha, Nebraska, who, she said, would deny women’s “basic rights and freedom.” As a state legislator, Mello had previously supported strict abortion regulations.

The attack produced the desired kowtow. DNC Chairman Tom Perez said, more or less, that Mello had come around to right thinking on the issue and that all Democrats are pro-choice now: “Every candidate who runs as a Democrat should do the same because every woman should be able to make her own health choices. Period.”

But at least one influential pro-choice Democrat isn’t ready to shut down diversity of opinion on the topic. On Sunday, House Minority Leader Nancy Pelosi, D-California, was asked by NBC’s Chuck Todd if her party still had room for anti-abortion members. Her answer bore no resemblance to what her party’s chairman said days earlier.

“Of course,” said Pelosi, whose roots go back to a Catholic childhood in Baltimore’s Little Italy. “I have served many years in Congress with members who have not shared my very positive – my family would say aggressive – position on promoting a woman’s right to choose.”

Pelosi’s pro-choice credentials are unimpeachable. So are her math skills. Polls consistently show that plenty of Democrats, including youthful ones, do not support unrestricted abortion rights. A CBS News poll in January found that a third of Democrats supported stricter limits on abortion.

To become speaker, Pelosi needs to flip two dozen House districts from Republican to Democratic in 2018. To win some of those seats, the party will need candidates capable of strategic shows of independence from the party line. Senate Minority Leader Chuck Schumer, D-New York, gets that, which is why he said on Monday that Democrats are a “pro-choice” party and a “big tent” party.

Democrats found a useful marketing tool when they settled on the phrase “pro-choice.” It embodies the principle – a woman has the right to choose – without casting anti-abortion views as illegitimate or intolerable.

The phrase gives breathing room to not only different views but the varied moral weights that Americans assign to abortion.

According to a 2016 Pew poll, one-third of Americans say abortion is not a moral issue. For them, perhaps, it’s a matter of women’s “health choices.” But most Americans, including many who identify as pro-choice, perceive abortion as an act with moral implications, requiring a political calculus that can incorporate a range of moral qualms. Roe v. Wade, the brilliantly muddled, still-enduring middle ground in the rancorous debate, is a reflection – and protector – of just such qualms.

As long as those qualms exist, efforts to enforce a rigid party dogma will be corrosive and self-defeating. Partisan polarization has sorted the parties into opposing camps on abortion. But there is still room in both parties for individual conscience to express itself. Efforts to extinguish that are bad politics. And maybe bad morality.