come down to the wire —(also: go down to the wire) continue to the very last moment or the very end:
- The game came down to the wire with the Eckerd defense stopping the Owls in the final minutes.
come under the wire —(also: go under the wire)
1. be at the finishing-line of a racecourse:
- He hardly ever came under the wire behind the other runners.
2. come at the last possible moment:
- The law suits were filed on New Year’s Eve, thus came under the wire as an event of 1941.