Reuters: President Barack Obama has expressed confidence a climate deal can be clinched as dozens of world leaders gather on Wednesday to try to break a deadlock at U.N. climate talks. “The president believes that we can get an operational agreement that makes sense in Copenhagen,” White House spokesman Robert Gibbs told a briefing in Washington on Tuesday, three days before a deadline on a new U.N. deal to combat climate change. Leaders including Venezuelan President Hugo Chavez, …