It wasn’t even close; it was a blowout. With an unexpectedly large turnout and a huge margin, Kansas voters on Tuesday rejected a measure that would have removed the right to an abortion from their state’s constitution. Nearly 60% of voters in the deeply conservative state rejected the anti-abortion measure. Only about 40% supported it.

The so-called Value Them Both Act would have dramatically devalued women in Kansas. The bill was designed to amend the state’s constitution in response to a 2019 ruling by the state supreme court, which found that abortion was protected in the state charter’s guarantee of “equal and inalienable rights” to all citizens. In contrast to the US supreme court, the Kansas court rejected the idea that civil rights were frozen in time at the time of the document’s ratification; instead, they extended those equal rights to women. “We are now asked: is this declaration of rights more than an idealized aspiration?” the court wrote. “And, if so, do the substantive rights include a woman’s right to make decisions about her body, including the decision whether to continue her pregnancy? We answer these questions, ‘Yes.’” Overwhelmingly, by a margin of roughly 20 points, Kansan voters agreed with them.

It was the first electoral test of support for abortion rights since the US supreme court overturned Roe v Wade in June, and the results were unambiguous. Even in conservative Kansas, abortion rights are popular with most Americans. Even in conservative Kansas, abortion bans are offensive to them.

On paper, this shouldn’t have been surprising. Americans have a wide range of opinions on abortion, but broadly, the notion that women and others should have a legal right to end their pregnancy is very popular, capturing somewhere between 60% and 70% support. Accordingly, ballot initiatives asking voters to restrict abortion tend to fail, according to New York Magazine correspondent Irin Carmon. A measure that would have granted personhood rights to fetuses and embryos failed in very conservative Mississippi in 2011. A municipal ballot measure that aimed to ban abortions after 20 weeks in the city of Albuquerque, New Mexico, failed by a large margin in an unusually high-turnout election in 2013. When South Dakota passed an abortion ban in 2006, pro-choice advocates managed to collect enough signatures to put the measure to a popular vote. The electorate threw that out, too.

The US supreme court’s ruling overturning Roe v Wade is particularly unpopular with the public, and has incited renewed passion for the pro-choice cause. According to polling from CNN, 63% of Americans – almost two-thirds – say they disapprove of the court’s ruling. A little more than half of them, 51%, say they disapprove “strongly”. This public outrage is clearly translating into votes. After the court reversed Roe on 24 June, many states saw a surge in new voter registrations. In Kansas, 70% of those new voters were women.

There were some indications that the anti-abortion side was nervous, even before their resounding defeat on election day. They played dirty. The vote was scheduled for a blindingly hot primary day in August, when turnouts are usually low and Republicans fare better. In the days before the election, a Republican-aligned firm in Nevada sent out texts to Kansas voters. “Women in Kansas are losing their choice on reproductive rights,” the texts read. “Voting YES on the Amendment will give women a choice. Vote YES to protect women’s health.” A yes vote on the constitutional amendment would have been a vote against abortion rights. Clearly, the anti-choice Republicans didn’t think they could win on the merits. Turns out, they couldn’t.

But you would never know how resoundingly popular abortion rights are from the behavior of the Democrats, who for the past three decades, and since the election of Donald Trump specifically, have been allergic to full-throated defenses of reproductive rights and other so-called “culture war” issues.

The party’s centrist leadership has made the calculation that only economic issues – defined, in practice, as issues that affect white men – can garner voters’ enthusiasm. The Biden administration was flat-footed and inept in its response to Dobbs, agreeing to take only the flimsiest and most risk-averse steps to restore abortion access and alienating huge swaths of its base as it attempted to keep the focus on its efforts to curb inflation. Biden hardly ever even says “abortion”. You get the sense he would much rather not be talking about it at all.

But the results in Kansas suggest that he should be. The ballot initiative on abortion produced a massive turnout. Abortion rights got considerably more electoral support than Joe Biden did in most Kansas counties. It’s a so-called “culture war” issue that brought voters out in droves to vote for a Democratic agenda item. The Kansas vote shows that the overturning of Roe has created a moral emergency that voters will respond to. Ignoring these “culture war” issues does not make the Democrats look sensible and moderate. It makes them look like cowards, running away from a fight.

What Republicans want to do to America, especially with regard to abortion rights, is unpopular. More importantly, it is anti-democratic and immoral. This is a fight that the voters want to take on. It’s time for the Democratic party to join them.

• Moira Donegan is a Guardian US columnist