The vote marks a sharp rebuke of Republican lawmakers who pushed the measure amid anger over abortion rights and other issues.

Amendment 4 would require any constitutional amendment put on the ballot through the initiative petition process to pass in all eight congressional districts, rather than by a simple majority. Missouri voters in recent years have passed amendments like abortion rights and marijuana legalization that were opposed by Republican lawmakers.

Kansas voters will decide on Amendment 1 this Tuesday to determine if Kansas Supreme Court justices should be elected via statewide races

Missouri’s proposed Amendment 4 would make it significantly harder to amend the constitution by requiring citizen initiatives to pass in all eight of the state’s diverse congressional districts instead of by a traditional, simple statewide majority. No other state has such a high standard — or has even asked voters to consider it.

The ballot measure calls for Kansas to abolish its current system for filling Supreme Court seats and switch to direct election of justices.

Constitutional amendment on Tuesday’s primary ballot could shift selection process away from governor’s appointment system

Supporters said the amendment gave more power to rural voters. Opponents, including small-town realtors, said it would do the opposite. Here are the vote totals.

Economist Stephen Moore discusses the economic growth potential of Missouri voting to end its state income tax on 'The Bottom Line.'