Time magazine on Wednesday named recently re-elected US President Barack Obama as its person of the year for 2012 - the second time it has accorded him the accolade.

With re-election as the first black president of the United States and a Nobel Peace Prize under his belt, Obama beat favored runners-up in the magazine poll, including Pakistani girls' rights activist Malala Yousafzai, to be enshrined again as Time's dominant personality of the year.

"We are in the midst of historic cultural and demographic changes, and Obama is both the symbol and in some ways the architect of this new America," Time Editor Rick Stengel told US television network NBC when he announced the selection on Wednesday.