Former Vice President Joe Biden's campaign team is going after Sen. Bernie Sanders (I-Vt.) for reportedly once going after Biden's old boss.The Biden campaign unveiled a new digital ad Monday that's tied to a story published The Atlantic last week that reported Sanders seriously considered launching a primary challenge against former President
Barack Obama in 2012. When word got around to the Oval Office, it reportedly sent Obama's re-election campaign team into a panic.Sanders' camp quickly denied the senator ever contemplated trying to unseat Obama, but regardless, the Biden team is unleashing the story against the new national frontrunner in a state where the former vice president is still considered the favorite. In the ad, they accuse Sanders of trying to undermine Obama's re-election, and argue he "can't be trusted" to build upon the president's legacy. Watch the full ad below and read more at Politico.