Casting new doubts into Venezuela’s chances of holding free and fair elections this year, President Nicolás Maduro said the recent discovery that opposition leaders had been plotting to kill him has done serious damage to the roadmap to a vote that both sides agreed to in Barbados in October. “The Barbados agreements are mortally wounded,” Maduro said on national television Thursday. “I declare they are in intensive care; they stabbed them; they kicked them. Hopefully we can save the Barbados agreements and move forward, through dialogue, to a great agreement of national consensus … without …