WASHINGTON—The Senate’s top Democrat will oppose Judge Neil Gorsuch’s confirmation to the Supreme Court and urged his Democratic colleagues to block the nomination.

On the Senate floor, Sen. Chuck Schumer of New York said that he couldn’t support President Donald Trump’s nominee, saying he feared he was insufficiently independent of the Trump administration and concerned about his testimony this week before the Senate Judiciary Committee and his history of decisions on the 10th Circuit Court of Appeals.

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