On Capitol Hill, Senator Mitch McConnell has dropped his demand that Democrats promise to preserve the filibuster, ending a standoff over a power-sharing deal between the two parties over how to run the divided chamber. McConnell made the announcement after two Democrats — West Virginia’s Joe Manchin and Arizona’s Kyrsten Sinema — expressed opposition to getting rid of the filibuster, which has been used over the years to uphold slavery and fight civil rights legislation.