Some good reporters at McClatchy are claiming that the President will go fairly big in Afghanistan.

President Barack Obama is nearing a decision to send more than 30,000 additional U.S. troops to Afghanistan next year, but he may not announce it until after he consults with key allies and completes a trip to Asia later this month, administration and military officials have told McClatchy.

As it now stands, the administration’s plan calls for sending three Army brigades from the 101st Airborne Division at Fort Campbell, Ky. and the 10th Mountain Division at Fort Drum, N.Y. and a Marine brigade, for a total of as many as 23,000 additional combat and support troops.

Another 7,000 troops would man and support a new division headquarters for the international force’s Regional Command (RC) South in Kandahar, the Taliban birthplace where the U.S. is due to take command in 2010. Some 4,000 additional U.S. trainers are likely to be sent as well, the officials said.

The first additional combat brigade probably would arrive in Afghanistan next March, the officials said, with the other three following at roughly three-month intervals, meaning that all the additional U.S. troops probably wouldn’t be deployed until the end of next year. Army brigades number 3,500 to 5,000 soldiers; a Marine brigade has about 8,000 troops.

You can bet that the President, if he announces this plan, will only count the combat troops and not the trainers and support staff. That’s the way this is typically done. But if you add up what McClatchy is reporting, you get to 34,000 additional Americans in the combat zone.

General McChrystal and other commanders have sought 40-45,000 more troops for Afghanistan; this would be a minor decrease from that. George Casey, the Chief of Staff of the Army, agreed with McChrystal on troop numbers today on ABC’s This Week.

This increase would be combined with efforts to crack down on governmental corruption in Afghanistan.

Generating public, congressional and international support for a troop increase will require heavy pressure on Afghan President Hamid Karzai to crack down on endemic corruption and drug trafficking, surrender more power to provincial and local governments and improve public services, the officials said. Karzai won a second term last week when his first-round election opponent bowed out of a run-off [...]

As McClatchy reported last week, the Obama administration has been quietly working with U.S. allies and Afghan officials on an “Afghanistan Compact,” a package of reforms and anti-corruption measures that it hopes will boost popular support for Karzai and erase the doubts about his legitimacy raised by his fraud-tainted re-election.

The troop announcement and additional steps will probably accompany yet another supplemental funding request, after the President promised that the most recent supplemental would be the last. The general assumption is that $1 billion would be needed for every 1,000 troops added to the battlefield. Carl Levin has already started preparing the ground for that request.

Senate Armed Services Chairman Carl Levin, who supports sending more trainers rather than combat troops to Afghanistan, predicted that a supplemental funding request would easily pass the Senate.

“I think there will be broad support for it in both parties,” said Levin, D-Mich.