Senator Walter Mondale's office was in the Russell Senate Office Building.
Senator Mark Dayton's biography says this:
"Mark's interest in public service led him to join the Washington
staff of then-Minnesota Senator Walter Mondale in 1975. He focused on
education, children and youth, and small business. Mark never dreamed
that a quarter-century later, he would inhabit his own office in the
same building as Senator Mondale once did."
Mark Dayton, U.S. Senator from Minnesota: Biography
Senator Dayton's office is in the Russell Office Building, according
to his contact page:
"Washington, DC Office
SR-123, Russell Office Bldg.
Washington, DC 20510"
Mark Dayton, U.S. Senator from Minnesota: Contact
Info about the Russell Building may be found here:
United States Senate: Senate Russell Office Building
My Google search strategy:
Google Web Search: "senator OR sen walter mondale" "office in the"
Google Web Search: "senator OR sen mark dayton" "office building"
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