Jansing was born to a Roman Catholic family[2] in Fairport Harbor, Ohio, the youngest of 12 children of Joseph and Tilly Kapostasy.

[4] She then accepted a position as a general assignment reporter for WNYT television in Albany, New York, where she quickly rose to become the weekend anchor and then the weekly co-anchor.

[3] While there, she won a New York Emmy Award in 1997 for her coverage of the Olympic Park bombing in Atlanta.

In 2008, she relocated to Los Angeles and worked as a field reporter for two years before returning as an anchor in 2010.

[7][8] On May 6, 2022, it was announced that with the move of MTP Daily to NBC News NOW, Jansing would take over the slot with her own hour of MSNBC Reports.