It is satire of dem logic since Bill Clinton.
Not even kidding, they call it median voter theory, and genuinely believe the best way to win an election is by 1. Promote the furthest right republican candidate. 2. Triangulate the dem candidate's positions to be 1 iota to the left of the republican.
This is how they justify compromised, means-tested policies instead of universal policies; the ones that provide immediate material improvements to people's lives are too far left, the ineffective policies that help nobody are more in line with what republican would want the dems to pass.
When this fails, they can only conclude that their policy was too far left.