The pro-Obamacare group Protect Our Care launched an ad Monday targeting Republican Susan Collins by anticipating a future in which the Supreme Court strikes down the healthcare law.

The ad, which will launch online and on TV in Maine, is meant to punish the Maine senator for being one of the deciding votes to confirm Supreme Court Justice Brett Kavanaugh. It imagines a future in 2019 or 2020 in which a case brought by Republican health officials makes it to the Supreme Court, striking down Obamacare in a 5-4 vote.

"Maine Sen. Susan Collins cast the crucial vote confirming Kavanaugh to the court," the ad says.

[Justice Kavanaugh: Collins and Manchin put him on Supreme Court]

The ad is drawing attention to the Obamacare lawsuit, known as Texas v. Azar, which was brought by 20 GOP officials who argue Obamacare must be undone because a key provision known as the individual mandate is zeroing out beginning in 2019. The individual mandate is a fine on the uninsured, and will be invalidated as part of the tax law passed by Republicans in Congress.

The Trump administration sided with Republican officials in the suit, but said that only the parts of the law that ban insurers from turning away sick people or charging them more should be struck down. The protections for pre-existing conditions, such as cancer or diabetes, were created in Obamacare and have been a rallying cry for Democrats ahead of the midterm elections.

The Texas case was heard by a federal judge on Sept. 5 and is awaiting a decision. It isn't yet known whether it will advance to the Supreme Court.

"Trump’s nomination of Brett Kavanaugh to be a rubber stamp on his war on health care was a true test of Senator Collins’s commitment to health care," Leslie Dach, chair of Protect Our Care, said in a statement. "Senator Collins failed that test, and Mainers will remember where she stood when the Court rules to rip health care away from us."

Collins hasn't announced her future political plans but she will be up for re-election in 2020 if she decides to run for Senate again.

The ad highlights Obamacare's protections for people with pre-existing conditions and says that it will allow insurance companies to deny coverage to half a million people in Maine.

Not everyone with a pre-existing condition would be affected by undoing the Obamacare protections. For the most part, the rules apply to plans that people purchase directly from an insurer. Most people in the U.S. get coverage through work or through a government program.