I largely agree with Ross:
...were I Obama, I would look at the left-liberal case against Webb - on the grounds that he's too anti-feminist, too pro-military, too skeptical about affirmative action and immigration, too hostile to Hollywood and academia - as an advertisement for the pick. An Obama-Webb ticket wouldn't send just a message that people who share the same ethno-cultural identity as Jim Webb can have a home in the Democratic Party, the way Kerry and Edwards were supposed to show that veterans and Southerners could too be Democrats; it would send a message that people with Webb's views can have a home in the party. It would lend substance to Obama's thus-far insubstantial claim to be something other than a party-line liberal, and in the process it would have the potential to achieve at the national level what the Congressional Dems have successfully done at the local level - namely, expand the definition of what it means to be a Democrat.