Matthews enthusiastically endorsed his wife's candidacy, and vowed to "offer Kathleen whatever help I can."

The longtime host of Hardball added: "As a journalist, I also know how important it is to respect certain boundaries on my support for her both in my public role and here on MSNBC. And while most of you know that our show doesn't typically cover congressional races, I will continue to fully disclose my relationship with her as part of MSNBC's commitment to being transparent and fair in our coverage."

In the ensuing months, Kathleen's name has rarely come up on Hardball. But many of the guests on the show have become generous donors to her campaign. And the transparency Matthews promised has not extended to mentioning that to his audience.