(AP) -- Five candidates, five states, five very different paths forward. The four men and one woman who would be president all head into Tuesday's primaries seeking different kinds of validation.

Donald Trump wants a knockout. Hillary Clinton is ready to end the long goodbye. Bernie Sanders needs a lucky break. Ted Cruz and John Kasich are road-testing a new alliance.

Polls in all five states close at 8 p.m. EDT. Delaware typically does the quickest count, with half its vote counted by a little after 9 p.m. Pennsylvania, Connecticut and Rhode Island should have half their vote reported by around 10 p.m., with Maryland getting there by 10:30 p.m. Delaware should have 90 percent of its votes counted before 10 p.m., Pennsylvania and Rhode Island by 11 p.m., Connecticut and Maryland closer to midnight.

Hillary Clinton keeps trying to leave Bernie Sanders behind, but he's not about to take the hint. With 384 Democratic delegates at stake, Tuesday's primaries offer Sanders one of his last, best chances to gain ground on Clinton -- but pre-primary polls didn't offer him much hope. Watch the tally at the end of the night: Clinton could emerge with 90 percent of the delegates needed to win the nomination. Going into Tuesday's vote, Clinton had 1,428 pledged delegates, Sanders 1,153. Factoring in superdelegates, Clinton had 1,944 and Sanders 1,192. It takes 2,383 delegates to win the Democratic nomination.

Expect Sanders to keep vowing to press on to California, which votes June 7. But watch his evening speech in Huntington, West Virginia, for any hints of resignation. Over the weekend, he allowed himself to be drawn into speculation over what Clinton would need to do to win over his supporters in the general election.

Trump needs a big delegate haul Tuesday to preserve his slim hopes of locking up the GOP nomination during the primaries. That's part of his "knockout" strategy for avoiding a contested convention. The candidate who likes to compare himself to a champion boxer eager to quickly end the fight has little margin for error. He headed into Tuesday's vote with 845 delegates, 392 short of the 1,237 needed to clinch. He needs to win 58 percent of all remaining delegates to lock it up. "I will make it," Trump says. "That's what we count on."

You know the movie plot: Two underdogs team up and go rogue; things don't end well for them. Ted and John are hoping their new alliance produces a better result than Thelma and Louise -- one not involving a plunge off a cliff. In an effort to stop Trump, they've agreed that Kasich will clear a path for Cruz in Indiana, and Cruz will do the same for Kasich in Oregon and New Mexico. Watch how the new arrangement plays out in the next few days: Cruz campaigns in Indianapolis on Tuesday; Kasich in Oregon on Thursday. How wide a berth do the candidates give each other?

Look for Trump, who'll speak from Trump Tower on Tuesday night, to dangle the Cruz-Kasich alliance as evidence of a corrupt political system and a sign of his own strength. The fact that his two rivals needed to join forces against him, Trump says, "shows how pathetic they are."

The state awards Tuesday's biggest chunk of Republican delegates, but it won't be a quick and easy matter to determine who gets them. The statewide winner gets 17 delegates. But the other 54 -- three from each of 18 congressional districts -- are directly elected by voters and don't have to commit to a specific candidate. The prospective delegates' names will be listed on the ballot with no information about which presidential candidates they support.

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