NOTUS:

Every year, the Democratic Congressional Campaign Committee designates a group of vulnerable Democrats as “Frontliners,” giving extra financial support to help them retain their seats. Frontliners also receive debate-preparation help and legislative and communications guidance. Unlike other members of the caucus, this group is also exempt from paying hundreds of thousands of dollars in dues to the DCCC because they’re expected to devote most of their resources to their own reelection campaigns.

After the U.S. Supreme Court weakened the Voting Rights Act by making racially drawn districts illegal this spring, state Republicans raced to remove majority-Black districts. Those efforts pushed some Democrats into red districts, lowering their chances of being reelected.

On top of that, the mid-cycle redistricting crunch has bulked up the number of Frontliners and other non-dues-paying members, multiple sources told NOTUS.