This post has been updated.

We know U.S. Sen. Jim Webb is backing fellow Democrat Tim Kaine in the former governor’s bid to replace him.

What we don’t know is how active Webb — who doesn’t much like campaigning for himself or anyone else, for that matter — will be for his friend as one of the most high-profile races in the nation heats up in the coming months.

Democratic Sen. Jim Webb of Virginia

But on Friday, Webb put his name on Veterans for Kaine, a list of more than 100 Virginia veterans and military family members backing the former governor, and sent out an e-mail to supporters on his behalf.

Kaine has said he would work to pick up where Webb left off on military and veteran issues. “Tim is committed to maintaining the respect for the service that America’s veterans have given to our country, often at great risk and personal cost,’’ Webb wrote.

Kaine is expected to face former governor and senator George Allen (R), whom Webb narrowly beat in 2006.

On Saturday, Webb’s office weighed in: “Of course Senator Webb is campaigning for Governor Kaine just as he campaigned for every Democratic representative across Virginia in 2010,” Webb spokesman Will Jenkins said.

So far, no events with Webb are scheduled. We’ll keep you posted.