In a public-private partnership to help thousands of seniors struggling to pay for prescription drugs, Maryland Gov. Martin O'Malley plans to announce today a deal with CareFirst BlueCross BlueShield to help cover those caught in a Medicare gap. The agreement would help seniors bridge the "doughnut hole," a much criticized cost-saving measure built into the Medicare prescription drug benefit passed by Congress in 2003. The program covers annual prescription costs up to a certain amount and costs above a higher threshold, but not those in between, leaving a hole in the middle of the coverage plan.