I wouldn't be surprised if Biden endorses Lamb, assuming he endorses anyone in the primary.
Biden said the Lamb reminds him of his son Beau, which he also said about Buttigieg.
While he is more moderate than Fetterman or Kenyatta, he wouldn't be another Manchin or Sinema. He'd be more like a Booker, Klobuchar, or Gillibrand.
Lamb's voting record is similar to Sinema's and Angus King's. Booker, Gillibrand, and even Biden when he was in Congress were way more progressive than him.
He seems like an unnecessary pain in office with a mixed record electorally having underperformed Biden last year.