What's potentially at stake in country's most expensive Supreme Court race

Tuesday's election for an open Wisconsin Supreme Court seat is set to sway not only the bench's ideological balance before a particularly impactful session but also how technically nonpartisan contests are waged in the coming years.

The court is currently split 4-3 in favor of conservative-aligned judges, but the race to replace retiring Justice Patience Roggensack could swing the court toward liberals for the first time in 15 years -- or hand the left another disappointing defeat in a state where Republicans have held many key offices since 2010.

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The candidates to take Roggensack's place are Milwaukee County Circuit Judge Janet Protasiewicz, a liberal-aligned jurist, and former Wisconsin Supreme Court Justice Daniel Kelly, aligned with conservatives. The race is already by far the most expensive state Supreme Court contest in history and comes before the court is predicted to take up cases over stringent abortion restrictions, state legislative maps and more.

And while the election is formally nonpartisan, meaning neither candidate is affiliated with a political party, they are each seen with distinct political leanings and outside groups have swamped the race with endorsements, ad buys and more to try and make clear where their allegiances lie.

That, in turn, has touched off a debate over how vocal nonpartisan judicial candidates -- who are the norm in the many states that hold elections for their courts -- should be on policies about which they could soon render decisions, especially at a time in which judges are seen as deciding controversial policy questions even in conflict with public opinion.

"It could not be bigger," Scot Ross, the former executive director of the liberal group One Wisconsin Now, said of the race's stakes.

Spending by both the campaigns and supportive outside groups has far outpaced past totals, with more than $42 million largely going toward ads in a contest without retail campaigning and raucous rallies.

While the overall money gap has narrowed, the Protasiewicz campaign itself has vastly outspent the Kelly campaign, giving her a leg up given discounted advertising rates for campaigns versus outside groups.

"The Protasiewicz campaign by far has the largest, biggest advantage, and has the entire campaign," Wisconsin GOP strategist Brandon Scholz said. "Other than probably the really diehard Kelly supporters, it has always been an uphill climb for the Kelly campaign."

Among the issues expected to come before the court after the election are Wisconsin's 1849 law banning nearly all abortions and, possibly, the state's legislative maps, which observers say Republicans drew to their advantage after taking state legislative power in 2010.

The general belief is that a Protasiewicz victory would lead to the scrapping of the abortion law and the creation of new maps, while a Kelly win could leave both the ban and the legislative lines in place.

Protasiewicz has said she personally believes abortion access should be available and that the current legislative lines are "rigged." Kelly has stayed away from commenting as directly on those issues, but he has won endorsements from anti-abortion groups and previously worked for the state GOP in private practice.

For his part, Kelly told ABC News that he feels "cautiously optimistic" about his chances and believes Wisconsinites will find appealing his unwillingness to discuss policies that could come before the state Supreme Court -- while claiming his opponent is forecasting her potential rulings and trying to politicize the election.

"As I go around the state of Wisconsin, I talk about nothing but the things that are relevant to the work of the court. So, talking about the constitution, the rule of law, judicial philosophy, where the authority comes from, the views of the court, how it reaches the court, what it takes to be a good jurist -- those are all the things that are talked about in my campaign," Kelly said. "Now, my opponent talks about none of them. All she talks about is the politics."

"There's a distinction between what you do as a jurist and the time prior to that, what you did as an attorney," he added when pressed about his record in private practice. "The question is not whether you have political views, it's whether you can effectively set them aside."

Protasiewicz's campaign denies that her comments on personal beliefs indicate how she'll rule on the bench while insisting that voters want to know the beliefs of candidates they elect to office.

"She's been very clear that these are her personal values: She believes in democracy, she believes in access to health care. But that's not saying how she's going to vote on these if they're before the court," campaign spokesperson Sam Roecker said. "I think part of this, as she's here on the campaign trail, is that voters expect to know some of the values of who they're voting for."

Critics say the election has become more about specific policy than about the law.

"The focus, of course, has been entirely on outcomes -- who will vote the way I want on abortion or redistricting -- when the rule of law in the United States is supposed to be focused on process. But process doesn't make for a very sexy 30 second ad," said ABC News legal contributor and former Trump Justice Department spokesperson Sarah Isgur.

"Our entire system depends on the process of the rule of law, and that's what I fear is really at stake in this race," Isgur said.

Others, meanwhile, suggest it was always overly optimistic to believe that politics would not color such races.

"I don't think we should be Pollyannaish about this," said Ross, the liberal advocate. "There are three branches of government. Each branch has politics, and to pretend that it's obscene to have politics in a political environment, I just don't agree with that."

The perceived political stakes have had the strategic value of driving interest in the candidates -- particularly in an off-year election, which typically sees lower turnout -- and future hopefuls are likely already taking note, operatives said.

"It now goes from a nonpartisan, who-gives-a-s--- race to a fall election where you're talking about issues," said Scholz, the GOP strategist. "On the Protasiewicz side of the campaign, it's all about issues. Dan Kelly has chosen not to do that. And somebody else can be the judge whether that was the right or wrong decision."

"I think the cat's out of the bag," Scholz added. "Once you've gone down this path, in the next election, there's going to be people that ask those candidates running for the court, 'What's your position on XYZ?'"