President Barack Obama plans to announce a redrawn battle plan for Afghanistan, including what the military says could be a roughly 50 percent increase in U.S. forces, in a national address Tuesday night from the U.S. Military Academy.

Although military and administration officials cautioned that Obama has not settled on a final figure, the military is planning for an increase of up to 35,000 troops begin next year. Military officials spoke on condition of anonymity because they are not authorized to discuss the president's plans.

The addition forces would come atop a record 71,000 U.S. troops in the country now and would represent the largest expansion since the war began eight years ago.

Obama will be speaking to a war-weary American public, with the Army's storied academy at West Point, N.Y., as a backdrop and cadets entering the service most stretched by two wars on hand. Polls show support for the war has dropped significantly since Obama took office, with a majority now saying both that they oppose the war and that it is not worth fighting.

Congressional Democrats may be an even tougher sell. The administration is deploying two Cabinet officials and the nation's highest-ranking military officer to explain the new Afghanistan plan in Capitol Hill hearings to begin Wednesday.

The president promised this week to "finish the job" begun eight years ago, and press secretary Robert Gibbs said Wednesday the announcement would include an exit strategy. But the surge in troops would be Obama's second since taking office, and liberal Democrats already are lining up against it, in part because of the also-surging cost _ up to $75 billion a year.

Secretary of State Hillary Rodham Clinton, Defense Secretary Robert Gates and Adm. Mike Mullen, chairman of the Joint Chiefs of Staff, are expected to appear before the Senate Armed Services and House Foreign Affairs committees on Wednesday. On Thursday, they would go before the Senate Foreign Relations and House Armed Services committees.

Congressional Democrats, including House Speaker Nancy Pelosi, D-Calif., have been blunt in saying Congress has little stomach for a large troop increase and flagging confidence in the U.S.-backed Afghan government the war effort is meant to support.

Pelosi and about 17 other congressional leaders from both parties were invited to the White House for a meeting with Obama late Tuesday before he goes to the military academy in New York.

Congressional Republicans, in particular, are more eager for the testimony that is likely to come the following week. War commander Gen. Stanley McChrystal and the U.S. ambassador to Afghanistan, Karl Eikenberry, are likely to appear on Capitol Hill on Dec. 8 or 9, officials said.