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- President Barack Obama

Obama is America's first black president. He became a state senator in 1997, and a U.S. senator in 2005.

Since becoming president, Obama passed the Affordable Care Act, remaking the national healthcare system, ended the "Don't Ask, Don't Tell" policy of barring gays and lesbians from openly serving in the military, and established the Consumer Financial Protection Bureau. Unemployment has remained above 8 percent throughout his term and he has yet to achieve his 2008 campaign promises to close the prison in Guantanamo Bay, Cuba; to pass the Employee Free Choice Act protecting labor unions; and to end Bush-era tax cuts.

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- Vice President Joe Biden

Before becoming vice president, Biden had served in the U.S. Senate since 1972, most notably as chair of the Senate Foreign Relations Committee.

As vice president, Biden has led the White House Task Force on Working Families and has had a key advisory role in the administration's strategy in Afghanistan. Biden was also put in charge of oversight for infrastructure spending from the Obama economic stimulus package.