This past week, a Democratic political consultant with longstanding ties to the party’s campaign committees quit a senior-partner position at the firm Deliver Strategies after it, like most dominant campaign outfits, agreed to comply with a Democratic Congressional Campaign Committee policy barring it from conducting business with a primary opponent of a sitting Democrat.

Her reason: She feared the policy’s impact on female challengers.

“It is hard enough for challengers, for a lot of reasons,” said the consultant, Amy Pritchard, who worked last year for Representative Ayanna Pressley, Democrat of Massachusetts, in her successful campaign to defeat a 10-term Democratic incumbent. “And this policy is a bridge too far. I’d like to see a majority of women in Congress, and it’s not going to happen with this policy.”