The Cruz-Kasich merger and four other things to watch in Tuesday’s primaries

Reporting from KENNETT SQUARE, Pa. —  Some are calling Tuesday’s batch of elections the “Acela primary,” after the high-speed train route that runs through all five states holding contests: Pennsylvania, Maryland, Delaware, Connecticut and Rhode Island. There’s good reason the name hasn’t caught on, however; these states vote so late in the primary season that they seldom attract much attention.

Not so this year, especially on the Republican side, which remains unsettled. Any of the states could play a crucial role in deciding whether front-runner Donald Trump gets his party’s nomination. Here are a few things to look out for:

The Cruz-Kasich merger debuts.

Sen. Ted Cruz of Texas and Ohio Gov. John Kasich pulled a Sunday night surprise, announcing that they were teaming up to prevent Trump from winning the nomination.

Kasich has agreed to stop campaigning in Indiana’s May 3 contest to give Cruz a chance to beat Trump there. Cruz has ceded Oregon and New Mexico, which vote later, to aid Kasich.

The pact does not include the states voting Tuesday. But it is a tacit admission that neither Cruz nor Kasich has much of a chance to notch any wins among them. Polls show Trump with a huge advantage in these states, and another thumping could further diminish the chance that the pact succeeds in preventing Trump from securing the nomination before the Republican National Convention this summer.

Bernie Sanders’ dwindling rationale.

For quite some time, the senator from Vermont has lacked a mathematical case that he can win enough pledged delegates to secure the Democratic nomination. What he has had is a rhetorical rationale, fueled by a string of victories in Wisconsin, Washington and elsewhere in recent weeks.

Then came New York. Hillary Clinton won there decisively last week, and Democrats intensified pressure on Sanders to ease his attacks on her, while stopping short of asking him to leave the race. Polls show Clinton ahead in Tuesday’s two largest states, Pennsylvania and Maryland. The three smaller states have not been polled as much, and results are tighter in the few surveys that have been taken. But even if Sanders wins one or two, he will endure more insistence from party leaders that he tamp down the fight against Clinton and perhaps even withdraw.

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Pennsylvania, the laboratory.

The biggest prize of the night will be a great place to examine exit polls for general-election hints.

The large swing state has almost every type of voter: diverse urban populations in Philadelphia and Pittsburgh where Democrats tend to rack up huge tallies; white working-class voters in the old manufacturing centers of Bethlehem, Erie and York being targeted by Trump and Sanders; conservative Christians in Lancaster and other rural communities who could give Cruz an opening; moderate suburban communities around Philadelphia that often decide statewide elections.

The state is also home to the much-discussed Reagan Democrats, Rust Belt whites who began voting for Republicans in 1980. Trump is already being partly credited for a 145,000 increase in new Republican registrations in the state since fall, including 61,500 Democrats who switched parties.

Despite the increase in GOP interest, Democrats continue to hold a registration advantage of nearly 1 million votes.

It’s the delegates, stupid. (OK, even smart people have trouble figuring it out.)

Pennsylvania’s Republican delegate process is among the most confusing in the country.

Of the 71 delegates at stake Tuesday, just 17 will be required to vote for the winner of the statewide Republican presidential primary on the first ballot of the national convention in Cleveland this summer.

The rest of the delegates, elected by district, are free to support whomever they want. It could take hours, if not days, after the results are announced to figure out which candidate those delegates plan to support in Cleveland. And their loyalties may change over time as they face competing pressures from voters, candidates and party insiders.

In other words, Tuesday’s vote does not really settle who wins the primary. That could give the state’s delegates unusual power in a contested convention.

The general election begins?

For weeks, political analysts have insisted that this or that primary could finally signal the beginning of the general election.

But it appears to be happening this time. After Trump’s and Clinton’s big New York victories last week, both front-runners began shifting into general-election mode, spending more time attacking each other than their respective primary opponents.

Neither candidate is likely to emerge from Tuesday’s primaries without a challenger. Trump still faces the threat that he will not secure enough delegates to win the nomination without a convention fight. Sanders has enough money and enthusiasm among his supporters to keep pushing his populist message.

Still, strong showings from Trump and Clinton on Tuesday could allow both candidates to spend even more time, money and rhetoric on the general election.

noah.bierman@latimes.com

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