The U.S. Supreme Court said today it will hear a challenge to President Barack Obama's Patient Protection and Affordable Care Act, with a decision likely to come next summer in the midst of a heated presidential election.

Opponents have called the new law, with its central mandate that almost all Americans have health insurance by 2014 or pay a penalty, an unprecedented expansion of the federal government.

The administration says it is confident the law will be upheld as a valid exercise of federal power, just as Social Security and the Civil Rights Act were found to be constitutional.

More than 30 lawsuits eventually were filed against the law after it was narrowly approved by Congress, which was controlled by Democrats in 2009.

"Throughout history, there have been similar challenges to other landmark legislation, such as the Social Security Act, the Civil Rights Act and the Voting Rights Act and all of those challenges failed," the Justice Department said in a statement in September when it asked the justices to consider the health-care act.

White House spokesman Dan Pfeiffer said today, "We know the Affordable Care Act is constitutional and are confident the Supreme Court will agree."

House Speaker John Boehner (R-Ohio) wrote the following Tweet on Twitter this morning: "Pleased to hear #SCOTUS will rule on ObamaCare. The #hcr law is destroying jobs in America & must be repealed."

Both the challengers and the administration urged the court to take the case, saying uncertainty about the law's constitutionality needed to be resolved as quickly as possible.

The public is divided over the idea of requiring all Americans to have health insurance, according to a new national survey. However, a CNN/ORC International Poll released today also indicates that support for the proposal, a cornerstone of the 2010 health care reform law, has risen since June.

According to the poll, 52 percent of Americans favor mandatory health insurance, up from 44 percent in June. The survey indicates that 47 percent oppose the health insurance mandate, down from 54 percent in early summer.

"The health insurance mandate has gained most support since June among older Americans and among lower-income Americans," said CNN polling director Keating Holland. "A majority of independents opposed the measure in June, but 52 percent of them now favor it."