On August 20th, 2020, Speaker of the House Nancy Pelosi endorsed Democratic Congressman Joe Kennedy in his ultimately unsuccessful primary challenge of Democratic Senator Ed Markey. This strikes me as unusual, since when Pelosi wades into a congressional primary, which she doesn’t always do, I’ve only seen her endorsing the incumbent.
My question is, is this Pelosi’s first ever endorsement of a primary challenger, or has she done so before?
The best example I'm aware of was in 2002, when redistricting in Michigan following the 2000 Census caused Rep. Lynn N. Rivers to lose her 13th district. The majority of its area was merged into the neighboring district, represented by fellow Democrat John Dingell, a Michigan representative for almost 50 years. Rivers challenged Dingell in the primary for the 15th district and was supported by Pelosi with a donation of $10,000.
This incident is described by Vincent Bzdek in his biography of Pelosi - Woman of the House: The Rise of Nancy Pelosi:
Her emphasis on holding people accountable was a break from the leadership of the immediate past, congressional observers said. “She is not afraid to tell people what she wants them to do and hold them accountable,” said one aide close to the Speaker. This is the “gavel” part of her leadership style.
She made a point of waving that gavel even before she was elected, when she contributed $10,000 to Lynn Rivers in a Michigan primary against the longest-serving House member, John D. Dingell, who had announced his support of Hoyer. Dingell complained that it was unprecedented for a member of the House Democratic leadership to favor one candidate over another in a primary.
Pelosi’s staff defended the donation by saying at the time it was given, it wasn’t clear that a new redistricting plan would pit Rivers against Dingell. The donation was handed out in September 2001, one day before the new district borders were signed into law. And it didn’t help Rivers much: Dingell won the primary anyway. Some of Pelosi’s allies, however, said she was clearly sending a message about loyalty, much the way she would a few years later when she backed her longtime ally John Murtha for majority leader, even though she probably knew he was going to lose. For many in the caucus, the contribution announced in no uncertain terms there would be retribution for disloyalty.
Apart from this, I'm not aware of any other instances where Pelosi supported a challenger to a Democratic incumbent in a primary for a congressional seat.
