Oregon, the first state to establish a presidential primary, was one of only about a dozen states that held presidential primaries as late as the early 1960s. Presidential nominees were chosen at conventions, but the handful of primaries were seen as important popularity contests that would figure in the decisions made by the party bosses.
Thus, Oregon was an important player in the presidential campaigns. And that's why you saw Dwight D. Eisenhower, who led the Allied forces in Europe in World War II, campaigning in Oregon before its 1952 primary.
Note that Eisenhower's motorcade is moving south along Southwest Broadway in Portland. You can see the sign for the Benson Hotel in the background, and Nordstrom's is near its current location.
It's hard to imagine a presidential candidate holding the same kind of event now. First of all, the Secret Service would veto it as a security nightmare.