Finally, the calendar also presents an opportunity for Mr. McCain. The Democratic convention ends on Thursday Aug. 28, and the Republican convention begins the following Monday. What better way for Mr. McCain to squash whatever lift Mr. Obama receives from his convention than to announce his choice for running mate just as Democrats are folding their tent in Denver? It would knock Mr. Obama to the back of the stage and give Mr. McCain a nice little lift going into his own convention. And yes, Republicans say that is something that is under very serious consideration in the McCain camp.