• Justice Anthony M. Kennedy announced that he would retire, setting the stage for a furious fight over the direction of the Supreme Court.

• President Trump said he would move quickly to name a replacement. He also said his nominee would be drawn from a list of 25 names that the White House issued in November.

• Mitch McConnell, the Senate majority leader, said the Senate would vote on a replacement this fall.

• Senator Chuck Schumer of New York, the minority leader, called on Mr. McConnell to delay a vote until after the midterm elections. But the Democrats have few options to actually block consideration of a nominee.