JEFFERSON CITY, Mo. - Former U.S. Rep. Cori Bush launches a comeback effort Tuesday during a Missouri Democratic primary that examines shifting American perspectives on relations with Israel, two years after progressive Squad member Bush lost to Wesley Bell.

The rematch in a strongly Democratic St. Louis area district ranks among several important primaries. Republicans in western Missouri select a nominee to challenge Democratic Rep. Emanuel Cleaver within a significantly altered district tied to President Donald Trump's push to keep a narrow House majority during the midterms.

Republicans in northern Missouri pick a possible successor for retiring Rep. Sam Graves, who leads the House Transportation and Infrastructure Committee.

At the same time, Missouri voters weigh two distinctive ballot measures supported by the Republican-controlled Legislature. One requires every citizen-initiated constitutional amendment to gain approval in each of the state's eight congressional districts rather than a simple statewide majority, a strict rule unmatched elsewhere. The second directs lawmakers to phase out the state individual income tax while expanding a state sales tax.

The matchup between Bush and Bell reveals how far the Democratic Party has moved in the past two years.

The well-funded American Israel Public Affairs Committee, which advocates U.S. backing for Israel, invested millions to defeat Bush in 2024 following her criticism of Israel's actions in Gaza after the 2023 Hamas attack. Bell again receives support from AIPAC.

Yet views on Israel have changed, especially among Democrats. A recent survey by The Associated Press-NORC Center for Public Affairs Research showed roughly 58 percent of Democrats now view U.S. support for Israelis as excessive, compared with 45 percent in an earlier AP-NORC poll from January 2024.

This primary may also measure the rising influence of democratic socialists, who have come from around the nation to aid Bush's campaign.

Bush and Bell developed their leadership abilities in Ferguson during the unrest after the 2014 police shooting of Michael Brown. Bell won a Ferguson City Council seat the following year and then beat a seven-term St. Louis County prosecutor in the 2018 Democratic primary.

Bush, a protest organizer, defeated longtime Rep. William Lacy Clay in the 2020 Democratic primary. She served two terms before losing to Bell.

Missouri became the second Republican-led state, following Texas, to follow Trump's request last year to redraw congressional districts for GOP benefit ahead of the midterms. The updated map extends Cleaver's former Kansas City district eastward into rural central Missouri, giving the new 5th District a Republican lean.

Cleaver faces no Democratic opposition. A six-candidate Republican primary includes state Sen. Rick Brattin, a Marine veteran and founding member of the Missouri Freedom Caucus, a conservative group that has questioned legislative GOP leaders. Brattin now holds endorsements from several top Missouri Republicans, including Gov. Mike Kehoe.

His chief rival in advertising has been Taylor Burks, a Navy officer and former Boone County clerk who managed elections in the home county of the University of Missouri.

Graves, who represented rural northern Missouri for 25 years, triggered a political contest by announcing in late March that he would not seek reelection. He backed conservative talk radio host Chris Stigall, a former Graves staff member.

The five-person Republican field in the GOP-leaning 6th District also includes Kansas City Council member Nathan Willett. Recent redistricting added more northern Kansas City neighborhoods to the large district. The Democratic primary features three candidates.

A constitutional amendment placed on the ballot by Republican state lawmakers would raise the bar for citizen-initiated amendments to pass. The proposal follows voter approval of several controversial citizen measures, including those protecting abortion rights in the state constitution, legalizing recreational marijuana, permitting sports betting and expanding Medicaid to low-income adults.

None of those measures would have succeeded under the proposed rule requiring citizen-initiated amendments to win majority support in every congressional district. Under Amendment 4, constitutional amendments proposed by the Legislature would still need only a statewide majority.

Amendment 5 would instruct the Legislature to gradually remove the individual income tax as state revenue increases. It would also permit lawmakers to raise revenue by broadening the sales tax to any goods and services, giving them five years to choose which sales to tax without further voter approval.

The Missouri proposal represents the first time since the modern income tax began more than a century ago that a U.S. state legislature has asked voters to eliminate the tax. Alaska remains the only state to impose a general individual income tax and later repeal it, doing so in 1980 through a legislative vote.

Massachusetts voters turned down income tax eliminations in 2002 and 2008 that originated from citizens rather than lawmakers.