When Scott Walker formalizes his presidential run Monday with a long-anticipated announcement, he will have at his side a seasoned veteran of Republican politics and an architect of the modern conservative movement. THE WEEKLY STANDARD has learned that Walker is expected to name Michael Grebe as campaign chairman as early as Friday. Grebe’s role, while not unexpected, is nonetheless a coup for Walker, who has firmly established himself as a first-tier candidate for the 2016 Republican nomination. Grebe served as chairman of both of Walker’s bids for governor, as well as Walker’s 2012 recall election – so he knows the...