EXCLUSIVE: Joe Biden's head of strategic communications, Kamau M. Marshall, has repeatedly posted sexist messages on social media over the past decade, beginning with a Christmas Eve 2011 tweet in which he expressed his affection for "power women" – as long as she "know[s] her place" and he can "where [sic] the pants." The social media posts are the latest example of a top Biden staffer undercutting the former vice president's public messaging. On Friday, Fox News reported that a supervising videographer on the campaign, Sara Pearl, openly called for defunding the police and tweeted a meme mocking officers as...