"If you're a quarterback out there, and you want to come play for the Raiders, give us a call," Jackson said Monday.
The Raiders have lost Campbell for a significant period of time to the broken collarbone he suffered when he landed on his shoulder at the end of a scramble late in the first half of Sunday's 24-17 victory over the Cleveland Browns. Campbell hopes to recover in time to play down the stretch for the Raiders this season, but they need help now with Boller and rookie Terrelle Pryor the only quarterbacks on their roster.
"It was a tough break," Campbell said. "I'm going to stay positive. If everything goes right, I could be back in six weeks."
The Raidershave looked into possible trades and free-agent signings that include names like Carson Palmer, David Garrard and Todd Bouman, among others.
"You just kind of rattle all the trees and see everything that's out there, what best fits us," Jackson said. "You've got to have somebody that can kind of hit the ground running, whether the guy can be a starter or the guy can be a backup because, if not, it's going to take two or three weeks, or four to get ingrained in the system, and you've fallen behind."
The injury spoiled what had been looking like a breakthrough season for Campbell. After bouncing between coordinators for most of his career, Campbell finally had a chance to play a second year in Jackson's offense and was making the most of it.
There's a good chance the Raiders will have to win this weekend against the Kansas City Chiefs with Boller under center. Boller, a first-round draft pick by the Baltimore Ravens in 2003, hasn't started a game in the NFL since 2009 with the St. Louis Rams. He has spent the past two years as a backup in Oakland, completing 10 of 18 passes for 125 yards with one interception.
Notes: The Raiders released CB Joe Porter to make room for Pryor on the roster. ... Center Samson Satele said he will play this weekend despite spraining his knee. ... Jackson said FB Marcel Reece is close to returning from an ankle injury, but DE Matt Shaughnessy could be out for a while still with a shoulder injury.
The Associated Press contributed to this report.