WASHINGTON — The unofficial race for the White House is being fought in a 12th floor suite of a building wedged between a Starbucks and a cross fit studio, five minutes' walk from the Oval Office.

There are no signs, no advertisements — no clue, really — that this is the nation's most powerful super PAC, except for a small gray nameplate next to two closed wooden doors and a keypad lock:

American Crossroads

Crossroads GPS

If you don't know them by name, they probably prefer it that way. The groups would not let a reporter inside last week.

But in Florida, you've no doubt seen their work on TV.

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