Oxon Hill, Maryland (CNN) President Donald Trump is the unquestioned king of this year's Conservative Political Action Conference. But with his throne on the line in 2020, the faithful here are already busy handicapping the Democratic field.

According to a very unofficial straw poll conducted Thursday and Friday morning, Sen. Elizabeth Warren of Massachusetts emerged as the potential challenger CPAC "voters" believe Trump would most assuredly outlast.

The question, posed to 75 respondees, was this: "Which Democrat considering a run in 2020 do you think Trump would be most likely to defeat?"

Twenty-two of them, so about 30%, chose Warren.

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