NEW YORK — Ever since it was signed into the law by President Obama on March 23, 2010, the Affordable Care Act has been under constant attack by Republicans seeking to undermine the former president’s signature legislation.

Despite surviving numerous attempts by congressional Republicans to repeal it and its constitutionality being upheld by a majority-conservative Supreme Court, the ACA, or Obamacare, may soon be facing its stiffest test yet.

In November, shortly after Americans choose their next president, the Supreme Court is scheduled to hear another case challenging the ACA — but this time the deck could be weighted even more to the right as President Trump’s nominee to replace Justice Ruth Bader Ginsburg is likely to be confirmed by the Republican majority in the Senate.

Even before the news of Justice Ginsburg’s death, Democrats have warned that Trump and his congressional allies have had their sites set on the ACA and now the spectre of a 6-3 conservative court has brought those fears front and center.

At question now is the argument by a coalition of Republican attorneys general from various states that the Republican-backed tax-cut law of December 2017 had rendered the ACA unconstitutional by eliminating the ACA’s penalty for not having insurance. That penalty is based on the ACA’s individual mandate that Americans must have health insurance or pay a fine. That argument is based on findings from lower courts that the individual mandate is essential to the ACA and without it the entire law is potentially unconstitutional as an improper use of Congress’ taxation powers. In 2012, however, when he sided with the liberal wing of the Court in upholding the ACA, Chief Justice John Roberts concluded that the ACA was valid, interpreting the individual mandate penalty as a constitutionally appropriate tax.

Even though most legal scholars, including several who challenged the law before the Supreme Court in 2012 and again in 2015, find the argument that the entire ACA should be discarded weak, U.S. District Judge Reed O’Connor in Texas accepted the GOP argument and declared the ACA unconstitutional in December 2018. Then, in December 2019, a three-judge 5th Circuit appeals court panel in New Orleans agreed that without the penalty imposed by the ACA the requirement to buy insurance is unconstitutional. However, the 5th Circuit sent the case back to Judge O’Connor finding that the entire ACA should not be struck down over this one provision in the legislation.

Democratic attorneys general, opting to not wait the months or years for Judge O’Connor and the lower courts to reconsider the challenge to the tax penalty, asked the Supreme Court to hear the case this year; and the Supreme Court agreed and has scheduled arguments for the week after the November election.

The fate of the ACA potentially puts at risk the health care of some 20 million Americans, including the very popular protection the law gives to those with preexisting conditions — a key component of Obamacare that has been only further accentuated in light of COVID-19 as those who have contracted the virus now fall into that group.