Ben Carson is starting to tumble ...
Retired neurosurgeon Ben Carson looks like he may be losing some steam in a slew of recent national and state polls that have shown clear warning signs for his candidacy.
A Fox News poll of Republican voters released on Sunday found Carson tumbling 6 points, dropping back down to 18% support.
Carson also has slumped in Iowa, the crucial first-nominating state where Carson has gained traction with the state's more conservative and evangelical groups.
According to a CBS poll released Sunday, Carson's support in the Hawkeye State has dipped to 19%. That put him below Trump, whose support sits at 28% in the poll, and Cruz, who garnered 21%. For Carson, it's a quick turn of events from last month, when he regularly surged ahead of Trump in Iowa polls.
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