"The Supreme Court made clear today that the American people will be the ultimate judge of Obamacare. As Republicans, we will redouble our efforts to repeal this job-killing law," U.S. Sen. John Cornyn, R-Texas, said in a statement.
"We must replace it with reforms that expand access and enhance care without adding trillions of dollars to the national debt and inserting Washington bureaucrats between Americans and their doctors."
House Speaker John Boehner, R-Ohio, said the healthcare law is hurting the economy and raising healthcare costs, making it more difficult for small businesses to hire.
"Today's ruling underscores the urgency of repealing this harmful law in its entirety," Boehner said in a statement.
"What Americans want is a common-sense, step-by-step approach to healthcare reform that will protect Americans' access to the care they need, from the doctor they choose, at a lower cost. Republicans stand ready to work with a president who will listen to the people and will not repeat the mistakes that gave our country Obamacare."
U.S. Senate Minority Whip Jon Kyl, R-Ariz., said the healthcare law has been "highly unpopular" with the American people for more than two years, particularly the mandate to purchase health insurance and other "tax hikes."
"Because the Supreme Court did not strike down the most onerous provisions, it appears that the American people themselves will have to overturn the law by the choices they make in November's election," Kyl said in a statement. "We need to listen to the people to see what they would like; then, Congress can replace the flawed law with reforms that ensure Americans have healthcare that is affordable with a doctor of their choice and without increased taxes, mandates and rationing."
Reince Priebus, chairman of the Republican National Committee, said in a statement the decision "sets the stakes for the November election."
"Now, the only way to save the country from Obamacare's budget-busting government takeover of healthcare is to elect a new president," Priebus said.
With the law, he said "unelected bureaucrats" now have "the unprecedented authority to come between elderly patients and their doctors."