Democrat said his campaign had been stalled while he was treated for prostate cancer

Colorado senator Michael Bennet jumped into the packed Democratic presidential primary race on Thursday, announcing a 2020 campaign for president that had been stalled while he was treated for prostate cancer.

Bennet, a former head of Denver public schools who has carved out a reputation as a policy-oriented moderate, made his announcement on CBS This Morning.

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The son of a former ambassador to India and a Yale law school graduate who worked in the Clinton administration, Bennet worked for Republican billionaire Phil Anschutz when he moved to Colorado in the late 1990s.

But when he re-entered public life, he did so as a Democrat, serving as chief of staff to then Denver mayor John Hickenlooper. Hickenlooper went on to become Colorado governor and now is also competing for the Democratic presidential nomination.

The presence of two moderate Coloradans who started their political careers in Denver city hall reflects how crowded the Democratic presidential field has become. Bennet’s understated style and distaste for the sound bites required in a political campaign have usually led to speculation that he would seek a cabinet position rather than try to become the next president.

But he began moving to assemble a presidential bid late last year and planned an announcement in April. He had to pause after being diagnosed with prostate cancer this spring.

Bennet, 54, told journalist Mike Littwin of the Colorado Independent that he would resume the campaign if he was treated successfully but that he wanted to make a point by disclosing his medical condition.

“I don’t want to be hysterical, but if it was left in me undetected, it could kill me,” Bennet said. “It won’t because I have insurance and decent medical care. The idea that the richest country in the world hasn’t figured out how to have universal healthcare is beyond embarrassing. It’s devastating.”

Bennet has been a vocal opponent in the Democratic party of the push for single-payer healthcare, so-called Medicare for All, championed by Vermont senator Bernie Sanders, another 2020 presidential candidate.