WASHINGTON – President Barack Obama plans to send 30,000 more troops to Afghanistan over six months, an accelerated timetable — with an endgame built in — that would have the first Marines there as early as Christmas, a senior administration official told The Associated Press.

With the full complement of new troops expected to be in Afghanistan by next summer, the heightened pace of Obama’s military deployment in the 8-year-old war appears to mimic the 2007 troop surge in Iraq, a 20,000-strong force addition under former President George W. Bush. Similar in strategy to that mission, Obama’s Afghan surge aims to reverse gains by Taliban insurgents and to secure population centers in the volatile south and east parts of the country.

In a prime-time speech to the nation Tuesday night from West Point that ends a 92-day review, Obama will seek to help sell his much bigger, costlier war plan by tying the escalation to an exit strategy, said the official who spoke on condition of anonymity. With U.S. casualties in Afghanistan sharply increasing and little sign of progress, the war Obama once liked to call one “of necessity,” not choice, has grown less popular with the public and within his own Democratic party. In recent days, leading Democrats have talked of setting tough conditions on deeper U.S. involvement, or even staging outright opposition. The 30,000 new U.S. troops will bring the total in Afghanistan to more than 100,000 U.S. forces by next summer. New infusions of U.S. Marines will begin moving into Afghanistan almost as soon as Obama announces a redrawn battle strategy.