WASHINGTON (AP) — Seven weeks ago, President Joe Biden laid out a lofty goal to vaccinate 70% of all American adults by July Fourth. The White House now acknowledges it will fall a little short of that target. Administration officials attribute their miscalculation to a combination of factors. They include the lessened sense of urgency that followed early success in the vaccination campaign as well as a decision to reach higher than a play-it-safe lower goal. They also encountered unexpectedly strong resistance among some Americans to getting a shot. Biden will be in North Carolina on Thursday urging Americans to roll up their sleeves.