was not helping their cause. On January 30, however, claims by the Johnson administration that a recent troop surge would soon bring an end to the war were severely discredited when the Tet Offensive broke out. Although the American military was eventually able to fend off the attacks, and also inflict heavy losses among the communist opposition, the ability of the North Vietnamese Army and Viet Cong to launch large scale attacks during the Tet Offensive's long duration greatly weakened American support for the military draft and further combat operations in Vietnam. A recorded phone conversation which Johnson had with Chicago mayor Richard J. Daley on January 27 revealed that both men had become aware of Kennedy's private intention to enter the Democratic presidential primaries and that Johnson was willing to accept Daley's offer to run as Humphrey's vice president if he were to end his re-election campaign. Daley, whose city would host the 1968 Democratic National Convention, also preferred either Johnson or Humphrey over any other candidate and stated that Kennedy had met him the week before, and that he was unsuccessful in his attempt to win over Daley's support.