"Let us await the result with tranquility, with hope, and above all with optimism that the future of Argentina will be better and more united," says center-left candidate Economy Minister Sergio Massa after casting his vote in the presidential runoff. Massa is facing the anti-establishment libertarian Javier Milei in a nail-biter election race. Polls show the candidates in a dead heat, with some 10 percent of voters undecided just days before the vote. IMAGES AND SOUNDBITES