WASHINGTON — Former Sen. Joe Manchin says a bipartisan deal to overhaul federal permitting rules for energy projects has a better-than-even chance of becoming law by the end of the year, after years of stalled efforts to cut through regulatory delays. “I think it’s well past 50%” that the measure will be signed, Manchin said in a recent interview. The West Virginia Democrat-turned-independent predicted President Donald Trump would support the agreement, saying both parties had worked hard on it and Republicans could explain its importance to him. The proposed changes would make it easier to expand the nation’s electric grid, bar administrations from blocking certain projects and establish less stringent deadlines for environmental reviews. The deal was reached between Manchin’s former Senate colleagues and the White House, according to Manchin. Manchin, who championed permitting reform during his time in the Senate, has twice failed to secure a deal. He urged current negotiators not to jeopardize the latest effort by holding out for a more sweeping agreement: “Don’t let the perfect be the enemy of the good.” Permitting reform has grown from a comparatively little-known Republican policy priority into a bipartisan goal, as lawmakers confront the hurdles involved in building energy infrastructure. The measure’s prospects remain uncertain until Congress acts, but Manchin’s forecast signals optimism that lawmakers could finally deliver a compromise after repeated setbacks.