My mom has been a Democratic machine operative in Boston since the 70's. She knows about Massachusetts politics, and she knows about this election. Here's what she says happened:
First of all, this is not a referendum on Obama or Washington.
This is about local infighting in the Massachusetts Democratic Party, plain and simple.
In this particular race, there has been a great deal of conflict between the Democratic insiders in Western Mass and the Democratic insiders in Boston.
During the primary, Western Mass backed Martha Coakley (who is from Western Mass) because her primary opponent, Mike Capuano, a current U.S. House Rep from Somerville, was from Somerville not Western Mass.
According to my mom, the Western Mass Democrats got a lot more momentum in the primary because no one in Boston believed that Capuano could lose. Western Mass turned out, Boston and vicinity did not.
Mom says Capuano would probably have won easily had he not lost the primary (he never has a serious challenge when he runs for his House seat).
Coakley, on the other hand, not only dropped the ball as everyone knows, but no politicians in Boston wanted their names associated with her after she won the primary. My mom isn't high enough up the chain to know why this is (or maybe she is holding out on me because she doesn't want anyone to read this and recognize her dishing the inside scoop - she is old school and thinks she shouldn't be talking publicly about this).
As the race went on, she (mom) asked around as to why she hadn't been called out to phone bank, check lists of registered voters, etc, for the campaign as usual. She was told "we're not backing anyone" by "someone on the committee" (she is not telling me what committee because this blogging thing is making her uneasy).
Menino never backed her publicly ("Don't name names!" says mom. "Everyone knows he's the mayor!" I say). He never backed her secretly either, the machine was not turned out for Coakley.
"Nobody likes her" says mom. What she means is, Coakley had no friends in politics. The Democrats in Massachusetts let this happen because - "I don't know" says mom.
Maybe they weren't about to let Western Mass manipulate them. Maybe it all comes down to nothing more than who is friends with whom.
All Scott Brown did was see an opportunity and turn it to his advantage.
There is no deeper national implication. This is not a death knell for the Democratic party or Obama. This is a story of a domestic spat between "parochial divisions" in Massachsetts.
The proverbial house divided among itself, fell.
UPDATE: Rec List! Thank you everyone, for listening to my mom's perspective.
UPDATE#2 A number of commenters are taking serious issue with the Western Mass/Eastern Mass thing. Mom did mention that this happens all the time, but after the primary everyone usually comes together. The coming together just didn't happen this time. Whether you accept that analysis as reasonable or not, one thing is certain. She didn't get called to campaign like she does for every other local, statewide, or national campaign. The machine volunteers did not deploy from Boston.
That doesn't mean that there was only one factor. As some have suggested, this was a "perfect storm." This campaign fell apart in many different ways - it wasn't just one thing. But it all goes hand in hand.
And one more thing: This is my mom. She is not "part of the problem." She is a tireless volunteer who has been working for decades to staff the polls, process voter registration lists, phone bank, travel to neighboring states for the national elections, and anything else she is called upon to do. As hostile as it gets around here somtimes, moms should be off limits! Insult me, but not my mom!