WASHINGTON -- Hillary Clinton replaced the longtime chief strategist of her struggling presidential campaign after the disclosure that he was working with Colombia's government to help win congressional approval of a trade pact that she opposes. The move comes two weeks before the pivotal Pennsylvania Democratic primary, where trade issues are likely to play a big role.

In a statement, campaign manager Maggie Williams said that "after the events of the last few days, Mark Penn asked to give up his role as chief strategist."...