Presidents traditionally have had great success when nominating justices to the Supreme Court, with confirmation being the norm and rejection being the rare exception. While the confirmation process usually ends with the nominee taking a seat on the Court, however, there is a great deal of variance in the amount of time it takes the Senate to act. To derive a theoretical explanation of this underlying dynamic in the confirmation process, we draw on a spatial model of presidential nominations to the Court. We then employ a hazard model to test this explanation, using data on all Supreme Court nominations and confirmations since the end of the Civil War. Our primary finding is that the duration of the confirmation process increases as the ideological distance between the president and the Senate increases. We also find evidence that suggests that the duration increases for critical nominees and chief justices and decreases for older nominees, current and previous senators, and nominees with prior experience on state and federal district courts.