Tancredo told 9NEWS he was riding his motorcycle on South Broadway in the Denver suburb of Littleton when he was cut off by a car entering the street from a parking lot.
"At first, I assumed it was a Democrat, but come to think of it, it could have just as easily been a Republican," Tancredo said in a text message to 9NEWS.
Tancredo said he wasn't wearing a helmet.
The 64-year-old said his glasses and watch were broken and his motorcycle was badly damaged.
"It sent me flying and the motorcycle flying about 40 or 50 yards along the ground," Tancredo said.
"It is the darnedest thing," he said. "I'm conscious. I'm just sliding along the pavement. It seemed like it was forever."
He said he went to a hospital later after doing a radio interview.
It wasn't immediately clear whether any citations were issued.
Tancredo, a former Republican congressman, switched his affiliation to the American Constitution Party and entered the governor's race after saying the GOP nominee, Dan Maes, couldn't beat Democrat John Hickenlooper.
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