Story highlights Obama almost left politics after his 2000 primary loss

He gave it one last shot when he ran for the US Senate

Washington (CNN) President Barack Obama opened up about a vulnerable and challenging time in his career that nearly led him to leave politics altogether in a wide-ranging interview with his friend and former senior adviser David Axelrod.

In 2000 -- four years before Obama won a seat in the US Senate and rose to the national stage at the 2004 Democratic National Convention -- the then-Illinois state senator was reconsidering his career in politics after suffering a bruising loss in the Democratic House primary race against Bobby Rush.

"That was a stage when I was really questioning whether I should continue in politics," Obama told "The Axe Files" podcast, produced by the University of Chicago Institute of Politics and CNN.

A 39-year-old Obama was broke after running a losing campaign, said he felt like "a third wheel" while attending the 2000 Democratic Convention, where, to add insult to injury, his credit card was declined, and was berated for not having the proper credentials to get into DNC after-parties.

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