Verrilli, 55, succeeded Justice Elena Kagan as Solicitor General of the United States in May 2011. He first served in the Obama administration as an Associate United States Deputy Attorney General, and until  he became Solicitor General, was serving as Deputy Counsel to the President.

Prior to working with Obama, he was a senior litigator with Jenner & Block. He's a Columbia Law School graduate and a Connecticut native.

Verrilli has said the individual mandate is the key part of the PPACA that can help the 40 million people that either don't have health insurance or can't afford it. Still, his job may be tough—even if they agree with the law in general, most Americans find the mandate unconstitutional and think the Supreme Court should, and will, rule as such.

Paul Clement

Paul Clement is the voice of the 26 states suing to overturn the health reform law.

The current Georgetown University law professor served for more than seven years in the U.S. Department of Justice, and served as Solicitor General for three years under George W. Bush.

Clement is certainly a high-profile lawyer: At just 45, he's argued nearly 60 cases before the Supreme Court. The Harvard Law graduate has done everything from defend President Bush's war on terror to represent NBA players in labor negotiations during the 2011 lockout.

In hearings so far, Clement called the mandate "an unprecedented effort by Congress" and said the requirement would force people, especially those who are young and healthy, to buy a product they don't want.