It was the most dramatic night in the United States Senate in recent history. Just ask the senators who witnessed it. A seven-year quest to undo the Affordable Care Act collapsed—at least for now—as Sen. John McCain kept his colleagues and the press corps in suspense over a little more than two hours late Thursday into early Friday. Not since September 2008, when the House of Representatives rejected the Troubled Asset Relief Program—causing the Dow Jones industrial average to plunge nearly 800 points in a single afternoon—had such an unexpected vote caused such a striking twist.

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