WASHINGTON - The Supreme Court decision upholding the 2010 health care law provided a huge political boost for President Obama, but it also serves up a fresh new campaign issue for races in Minnesota and across the nation.

Ruling that the law's controversial coverage mandate can survive as a tax, rather than as a governmental power over interstate commerce, the high court on Thursday reshaped the debate over the landmark law that extends health insurance to 30 million more Americans.

"It's official," said Minnesota GOP Senate candidate Kurt Bills, who is challenging DFL incumbent Amy Klobuchar. "Klobuchar voted for the largest tax increase since the imposition of the income tax."

Democrats refute the tax increase claim, saying the act will save money over time. Klobuchar, like many congressional Democrats, focused on the plan's benefits, such as closing the coverage gap for seniors' prescription drugs, letting young people remain on their parents' plans until age 26, and ensuring that people with pre-existing conditions are no longer denied access to health insurance.

"There are some people who can afford insurance who don't buy it," said Klobuchar, adding that Americans pay a steep price for the health care costs of those without insurance. "We are all paying for them."

The court decision was a stinging rebuke to vocal Tea Party critics like U.S. Rep. Michele Bachmann, R-Minn., who based her run for the presidency on repealing what she and other Republicans call "Obamacare."

Outside the Supreme Court on Thursday, Bachmann told a Tea Party crowd, "We will not forget in November!"

Less than 20 feet away, Rep. Keith Ellison, D-Minn., and other members of the Congressional Progressive Caucus celebrated the ruling. "One of the people ... on the right wing said, 'It's not over,'" Ellison said. "She's quite right about that. We need to think about how we can make health care even more affordable. I look forward to a day when we [have] Medicare for all."

House Republicans plan a repeal vote in coming weeks, but it would be unlikely to pass the Democrat-led U.S. Senate.

"Elections have consequences," said Rep. John Kline, Minnesota's highest ranking Republican in Congress. "There's no question this will be an election year issue at all levels."

State legislators say they're already gearing up for the fight.

"Politically, this is probably the best thing that could have happened," said state Sen. Sean Nienow, R-Cambridge, who is on the Health and Human Services Committee. Nienow said the decision to uphold the Affordable Care Act could be better for the conservative movement in the long run than if the individual mandate had been struck down. "It fires up the base," he said. "This could be a victory for those of us who oppose this law."

Others say the time to refight old battles is over. Bachmann's DFL opponent, Jim Graves, in a refrain common among Democrats on Friday, said that "now is the time for the country to move forward."

While Republican governors such as Wisconsin's Scott Walker said they won't participate until the next election, DFL Gov. Mark Dayton hailed Thursday's ruling, which he said clears the way for Minnesota to implement the Affordable Care Act.

"We have long been a national leader in health care reform," he said, "A reputation that will be enhanced as we work with private and public sector leaders to implement the Affordable Care Act in Minnesota."

Sen. Al Franken, D-Minn., said the debate now will center more on what is in the law. "As people see what's actually in the law," he said, "It will gain support."

Democrats say the decision also lifts the legal uncertainty around the law, allowing doctors, hospitals, drugmakers, insurers and patients to plan for the far-reaching changes set to take place in 2014.

"I can tell you, the American people are sick of the arguments," said U.S. Rep. Tim Walz, a Democrat whose district includes Rochester's Mayo Clinic. "They're sick of the debate."

But Republicans say the court's ruling has reframed the debate around taxes. The majority upheld the law specifically under Congress' taxing powers.

"OK, it's a tax," said Kline, even as he disagreed with the court's ruling. "And it's a monster."

Staff writer Jennifer Brooks contributed to this report. Kevin Diaz is a correspondent in the Star Tribune Washington Bureau.