AP Photo/Patrick Semansky Maryland Governor Larry Hogan delivers remarks at the mayoral inauguration ceremony for Catherine Pugh inside the War Memorial Building in Baltimore, Tuesday, December 6, 2016. W hen Labor Secretary Tom Perez announced in mid-December that he was jumping into the race for Democratic National Committee chair, analysts immediately began to speculate what his motivations could be for challenging Minnesota Congressman Keith Ellison. Ellison had already been in the race for a month , and had received diverse endorsements from the AFL-CIO , Elizabeth Warren , Chuck Schumer , among many others. Was the White House putting Perez up to this, nervous about a key Sanders supporter leading the party? Was this about preserving support from billionaire donors like Haim Saban, who said electing Ellison would be a “ disaster ” for Democrats? And, wait, wasn’t Perez—a former Maryland state official and a longtime resident of the D.C. suburbs—considering a 2018 run against...