PHILADELPHIA: Democratic White House nominee Hillary Clinton surprised ecstatic delegates Wednesday by striding out onto the stage of her party’s national convention as President Barack Obama wrapped up his primetime speech. To the strains of Stevie Wonder’s “Signed, Sealed, Delivered,” Obama shared a warm embrace with his would-be successor, capping an all-star night that included appearances by Vice President Joe Biden, Clinton’s running mate Tim Kaine and independent Michael Bloomberg, the former mayor of New York. “This year, in this election, I’m asking you to join me — to reject cynicism, reject fear, to summon what’s best in us, to elect Hillary Clinton as the next president of the United States,” Obama said as he concluded his remarks.