Six contenders in Super Tuesday II primaries in Missouri, Illinois and three other states each face challenges and opportunities.

Polls will be open from 6 a.m. to 7 p.m. in Missouri and Illinois. Florida, North Carolina and Ohio also have primaries.

Democrats

Hillary Clinton

Best Case — She sweeps all five states, lengthens her delegate lead of more than 2-1 and escalates calls within the Democratic Party to rally around her as the nominee.

Worst Case — Clinton falters in one or more states, and Sanders cuts into her delegate lead. Doubts grow about her trustworthiness and appeal, especially to younger voters and more liberal Democrats.

Bottom Line — She’s still in control, but needs to keep winning.

Bernie Sanders

Best Case — The socialist Sanders’ appeals on trade and economic inequality sweep him to surprising victories in the three Midwestern states.

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Worst Case — Clinton tromps him across the map, and any momentum Sanders gained last week in an upset in Michigan is gone.

Bottom Line — Sanders needs a win someplace Tuesday night to remain on the viability radar.

Republicans

Donald Trump

Best Case — He secures the winner-take-all delegate gold mines of Ohio and Florida, knocking out favorite sons John Kasich and Marco Rubio.

Worst Case — Trump loses Ohio and Florida, which would blunt his momentum and suggest he would be a poor general election candidate in vital swing states.

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Bottom Line — He needs to pull away or face an extended fight right through the July convention.

Ted Cruz

Best Case — He stays close to Trump in the delegate race by winning Missouri and picking off delegates in Illinois and North Carolina.

Worst Case — Trump pads his delegate lead by several hundred by sweeping the five states, leaving Cruz without a path to the nomination.

Bottom Line — Missouri is key for Cruz. Polls suggest it is his best chance to beat Trump and cling to his claim to be Trump’s primary opponent.

Marco Rubio

Best Case — Rubio holds his home state of Florida and picks off a few delegates elsewhere to walk back from the brink.

Worst Case — He loses Florida — and any reasonable cause to continue.

Bottom Line — It’s all about home cooking for Rubio.

John Kasich

Best Case — The Ohio governor beats Trump at home, allowing Kasich to stay alive for winner-take-all contests in California, New Jersey and Pennsylvania.

Worst Case — He loses Ohio, and the only path is home for good.

Bottom Line — Like Rubio, survival is all about winning his home turf.

Contact Chuck Raasch — 202-298-6880, @craasch on Twitter or [email protected]

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