Supporters wave party flags of Luis Guillermo Solis, presidential candidate of the Citizens' Action Party (PAC), as they march through the streets, during the presidential election run-off in San Jose April 6, 2014. Solis, a center-left academic who campaigned on a popular anti-corruption message and has never been elected to office, is expected to win Costa Rica's presidential run-off on Sunday after his opponent slid in polls and stopped campaigning. REUTERS/Juan Carlos Ulate (COSTA RICA - Tags: POLITICS ELECTIONS TPX IMAGES OF THE DAY)