Iran is trying to avoid detailed commitments. The French are sticking to their tough line. And U.S. President Barack Obama faces a battle to sell any deal to a skeptical Congress. Despite those and other obstacles, negotiators appear increasingly likely to clinch an historic deal to restrict Iran’s nuclear program for at least a decade in exchange for relief from sanctions, Western and Iranian officials said. U.S. officials, including Obama, have long said they see at best a 50-50 chance of getting a deal with Iran. That remains the official line, but diplomats close to the talks tell Reuters the chances are higher than that as foreign ministers and other negotiators head to Vienna next week for the final stage of a nearly two-year process. Driving the cautious optimism, they say, is not so much progress made in overcoming sticking points as the intense political pressure on […]