Story highlights Former New York City Mayor Michael Bloomberg commissioned a poll last month to see how he would fare as a third-party candidate, a source close to the former mayor said

The source said Bloomberg commissioned the poll after watching the meteoric rise of political newcomer Donald Trump

Washington (CNN) Former New York City Mayor Michael Bloomberg commissioned a poll last month to see how he would fare as a third-party candidate against Hillary Clinton and Donald Trump, the respective Democratic and Republican presidential front-runners, a source close to the former mayor told CNN Saturday night.

The source said Bloomberg, a billionaire media executive, commissioned the poll after watching the meteoric rise of political newcomer Trump over the past six months. But the source did not discuss the poll's findings.

News of the poll was first reported by The New York Times.

White House whispers surrounding Bloomberg, a longtime Democrat who switched to the Republican Party to seek the NYC mayoralty in 2001, but who ran for his third term as an independent, are not new, and he remains a nationally recognized political figure.

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