Candidates vying to carry the banner of Venezuela's opposition in presidential elections next year agreed at a debate on Wednesday that they must present a united front against the ruling party and work to boost the economy by attracting private investment. The debate, the first between opposition hopefuls since 2011, was held as they await a ruling by the country's top court which could suspend the Oct. 22 nominating contest. Independent candidate for 2024 Luis Ratti - who many in the opposition say has ties to the ruling socialist party - asked the Supreme Justice Tribunal on Monday to bar the primary on unspecified allegations of irregularities.