Vice President Joe Biden rallied support for President Barack Obama before the nation's largest civil rights organization on Thursday, telling the NAACP that Obama has the "character of his convictions."

Biden drew cheers as he credited Obama for championing a landmark health care law, launching the mission that killed al-Qaida leader Osama bin Laden and stepping in to rescue the financial system and U.S. automakers General Motors and Chrysler.

"He has put country first," Biden said.

Biden addressed the annual convention of the National Association for the Advancement of Colored People a day after Republican presidential candidate Mitt Romney said he'd do more for African-Americans than Obama, the nation's first black president. Romney was booed when he said he'd repeal Obama's sweeping health care reform law but otherwise got a polite reception as he reached out to a traditionally Democratic voting bloc.

The vice president countered that Romney's policies would hurt black working families, and he outlined detailed differences between Obama and Romney on health care, education, energy, women's rights and research.

NAACP members offered a rousing reception, yelling "no!" after Biden said near the end of his speech: "Let me close, my friends."