MIAMI (AP) — Venezuela’s opposition is rallying behind an unknown former diplomat to challenge Nicolas Maduro in this summer’s presidential election, the latest gambit to unseat the self-declared socialist, whose lock on power seems all but assured.

On Friday night, all 10 parties in the chief opposition coalition announced they would back Edmundo González to be their candidate on the July ballot. Within hours, a catchy campaign jingle set to salsa music started circulating on social media declaring “Todo el mundo con Edmundo” — “The entire world with Edmundo.”

The surprise show of unity adds to mounting international pressure on Maduro and his allies to allow Venezuelans a free and fair vote to decide who they want to lead the oil-rich South American nation for the next six years. Polls show that if given half a chance, Venezuelans would overwhelmingly vote to boot Maduro from office.