The actor will play Bob Little in several episodes of the NBC drama, TV Guide reports.
Bob, who used to work as an intern for Kristina (Monica Potter) and is described as "frighteningly young and attractive", is now running for office and hires her to help out with his campaign.
Amber (Mae Whitman) is also expected to get involved with the race.
Tucker previously played Tommy in The Black Donnellys and has also guest starred in shows including Royal Pains, Criminal Minds, White Collar and Six Feet Under.
The third season of Parenthood, which has been extended by two episodes, airs on Tuesdays at 10/9c on NBC.
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