@tsarstepan,
I had not heard of him before. Of course when former NY governor David Paterson pushed Kirsten Gilibrand into the filler spot of Hillary Clinton the majority of people, including New York State residents had no idea who she was.
As to Cowan running in the June election, according to this item, one of Governor Patrick's decision making factors was to get someone with no intention of running in the special election.
http://abcnews.go.com/Politics/wireStory/mass-gov-picks-aide-cowan-interim-senator-18353865
Quote: William "Mo" Cowan, former chief-of-staff to Democratic Gov. Deval Patrick, was tapped Wednesday to serve as interim U.S. senator for Massachusetts until a special election can be held this summer to fill the seat left vacant by John Kerry's confirmation as the nation's new secretary of state.
Cowan, 43, became chief-of-staff to Patrick in 2010 after serving as chief legal counsel during the governor's first term. He stepped down as Patrick's top aide in December, though he remained on as a senior adviser through the filing last week of the governor's state budget request.
Cowan said he was "honored and humbled" by the appointment, and pledged to work as hard as possible to serve the state during the interim period. The special election to select Kerry's permanent replacement is June 25.
Patrick had said that diversity would be an important consideration in his choice of an interim senator, and Cowan will be the state's second African-American senator. Edward Brooke, a Republican, represented Massachusetts from 1967-1979.
The governor had also said that his selection would be a person who had no intention of being a candidate in the special election, but otherwise he had given little indication...