A local blood center is trying to stock up in time for the Democratic National Convention. Officials with the Bonfils Blood Center said Monday that the number of blood donations typically drops by as much as 20 percent during the summer months. The annual decline in giving will coincide with the Democrats' convention, Aug. 25-28 in Denver, when it's essential to have a ready supply of blood in the event of an emergency, officials said. "We definitely are taking steps to prepare for it (the convention)," said Jessica Maitland, Bonfils Blood Center's vice president of marketing and community operations. "We've...