TOPEKA, Kan. (AP) — Republican lawmakers in Kansas failed to get a proposed anti-abortion amendment to the state constitution on the ballot Friday, and abortion opponents responded by moving aggressively to block a Medicaid expansion plan backed by Democrats and GOP moderates.

Neither side expected Friday's vote in the Kansas House to be the last word on whether the abortion measure ultimately is put to a vote in a statewide election, when a simple majority would change the state constitution. It would overturn a Kansas Supreme Court decision last year that declared access to abortion a "funda...