Republican candidates take the stage for the second GOP debate.
The early debate among the second-tier of Republican candidates for U.S. president is under way, with each of the candidates targeting party frontrunner billionaire Donald Trump.
Four lower-ranked candidates -- Louisiana Governor Bobby Jindal, South Carolina Senator Lindsey Graham, former Pennsylvania senator Rick Santorum and former New York governor George Pataki -- squared off in California Wednesday.
Jindal took first aim at Trump, challenging his conservative position and asking his party to stop treating Trump like a Republican. Pataki said Trump is "unfit to be president."
Graham focused his attention on Islamic State. Mentioning his service in the U.S. Air Force, Graham said he is best qualified to be the commander in chief and knows what it will take to defeat the terrorist group in Iraq and Syria.
Later in the day, real estate titan Trump will be at center stage during the second Republican presidential debate, with 10 opponents trying to cut into his lead for the party's 2016 nomination.