Roll Call Group, a wholly owned subsidiary of The Economist Group, has acquired Congressional Quarterly (CQ) in a move to cement its hold on the DC political market. Terms of the deal were not disclosed. CQ, a magazine for Congressmen and other DC insiders, and its Web site, will join the newly formed CQ-Roll Call Group, which also includes 2008 Roll Call acquisition Capitol Advantage, the weekday daily Roll Call magazine, CongressNow wire service and other content sources.