The deal, if finalized, would give the Raiders two former Heisman Trophy-winning quarterbacks from USC, and it is expected that Leinart, not former third-round pick Terrelle Pryor, would be Oakland's primary backup to Carson Palmer.
Many around the league believed Pryor had the inside track on the Raiders' backup quarterback job. But a new Raiders front office and coaching staff have targeted changes at the position, sources have said.
Leinart has a familiarity with Oakland's offensive system because new coordinator Greg Knapp was his quarterbacks coach in Houston. Leinart also has a relationship with Palmer, whom he backed up to start his college career at Southern California.
After winning two national titles, winning the 2004 Heisman Trophy with the Trojans and being the No. 10 overall pick in 2006 by Arizona, Leinart has failed to meet expectations. He started 11 games as a rookie with the Cardinals but only seven games in the past five seasons. He lost the starting job in Arizona to Kurt Warner in 2008.
He got a chance to start last season with the Texans after Matt Schaub broke his right foot, but Leinart dislocated his left shoulder in the first half against Jacksonville on Nov. 27, ending his season.
In 31 career games, Leinart has completed 57.6 percent of his passes with 15 touchdowns, 20 interceptions for a 71.6 passer rating. He has won eight of his 18 career starts.
Information from The Associated Press contributed to this report.