?It?s earth-shattering?: Democrats and allies vow midterm fight over abortion

With the US supreme court seemingly poised to exploit its conservative supermajority to undermine or overturn the landmark Roe v Wade decision, Democrats are vowing to make abortion a defining issue of next year's midterm elections, embracing what they view as a political silver lining in an otherwise nightmare scenario.

As the justices weigh whether to uphold a Mississippi law banning most abortions after 15 weeks, far earlier than Roe allows, and a request by the state that they explicitly overturn the historic 1973 ruling, Democrats and their allies have promised a fight.

Across the electoral battlefield, they are kindling what they hope will be a political reckoning over abortion.

"It's earth-shattering," said Jenny Lawson, vice-president of organizing and engagement campaigns for Planned Parenthood Action Fund. "The court's actions are going to change the way people think about reproductive freedom and how essential it is. It will be a driving force of the election, undoubtedly."

During oral arguments on Wednesday, the six conservative justices on the nine-member bench signaled they were comfortable with Mississippi's abortion law, despite the precedent established by Roe in 1973, affirmed in 1992, that women have a right to end their pregnancy until the point of fetal viability, at about 24 weeks.

That law has been blocked by lower courts and the state appealed. The case, Dobbs v Jackson Women's Health Organization, pits Mississippi against the last abortion clinic in the state.

Several justices appeared willing to overturn Roe entirely, in what would be a momentous decision allowing states to govern the procedure, though the signals were less clear on that pivotal point.