Obama's offensive caught the Romney camp completely by surprise and left them flat-footed and slack jawed.
There, so taken, caught in the act, flat-footed, we are obliged to make our stand.
What we want here, sir, is straight-out, flat-footed hell—the burnin' lake o' fire an' brim-stone.
In a little while, with flat-footed stamping, Ben Helders came in.
Plan' ti grade, walking on the soles of the feet; flat-footed.
Or by bold combinations: down-and-out, up-state, flat-footed.
By wetting the foot one can see readily whether he is flat-footed by the imprint made.
I'd like to take a flat-footed stance as claiming that the end justified the means.
Then she must be used to flat-footed Finn servant girls, declared Ruth gaily.
They are bilt sumthing like a hen, and are an up-and-down, flat-footed job.
c.1600, "with flat feet;" meaning "unprepared" is from 1912, U.S. baseball slang, on notion of "not on one's toes;" earlier in U.S. colloquial use it meant "straightforwardly, downright" (1828), from notion of "standing firmly."
Unprepared; surprised •Usu in the phrase catch someone flatfooted: He just stood there flatfooted and watched it roll in (1912+ Baseball)
Straightforwardly; without ceremony: If they were going to turn it down, they would have just flatfooted done it (1828+)