[2][3] Legum earned a Bachelor of Arts in Public Policy analysis from Pomona College and a Juris Doctor from Georgetown University Law Center in 2003.

[5] Legum founded ThinkProgress in 2005,[6] running it for two years before leaving in 2007 to join Hillary Clinton's presidential campaign as research director.

He says his newsletter is about politics and power, though he has covered many topics including corporate donations to politicians and Facebook's struggles with its advertising guidelines.

He seeks out stories he thinks media outlets won't be covering and does a deep analysis, focusing on national issues.

Legum's business model is to attract paying subscribers through delivering in-depth reporting while eschewing ad dollars, and the newsletter contains no advertising.