What to watch for in Tuesday's primaries

Hillary Clinton plans to speak at the Convention Center on Tuesday after results in the five-state "Acela primary" become clear. She'll be on a stage about seven miles from the site of the Democratic convention in July. Coincidence?

Hardly. Clinton hopes to reinforce the message she's been sending for the last week: The nomination fight with Sen. Bernie Sanders is over. She won't say it, of course - focusing instead on GOP opponents Donald Trump and Sen. Ted Cruz - but the setting and the expected results could speak loudly enough.

If the polls are right, Clinton is poised to sweep all five states Tuesday, as is Trump.

Here's what to look for as the returns for Pennsylvania, Delaware, Maryland, Connecticut, and Rhode Island roll in (more detailed analysis below):

1. What's Hillary Clinton's margin of victory, and how does Bernie Sanders react?
2. Can Donald Trump appeal to educated, suburban Republicans in the Philadelphia and the Lehigh Valley?
3. Will the Democrats' positions on gun control sway Connecticut voters?
4. Will Pennsylvania voters figure out which delegates support their favored candidate?
5. Will black voters turn out in Philadelphia?
6. Can John Kasich win his hometown outside Pittsburgh?

The Vermont senator isn't expected to concede regardless of Clinton's vote haul, but Democrats will be keen to see whether he tones down his attacks on the front-runner as her lead widens.

Sanders' campaign manager, Jeff Weaver, has talked about fighting on through the primaries, then trying to cajole hundreds of superdelegates into switching their allegiance from Clinton to Sanders. Senior strategist Tad Devine, however, has been hinting that Sanders might "reevaluate" after the Northeastern states vote Tuesday.

Can Trump make inroads with more educated Republican voters, particularly in the Philadelphia suburbs and the Lehigh Valley?

Exit polling has identified Trump's core support as disaffected, less-educated and less-affluent white middle-age voters who are worried about their economic circumstances. Across all the states with data available, Trump was supported by 35 percent of college graduates, lower than his 47 percent level of support among those with a high school education or less.

Christopher Borick, a pollster at Muhlenberg College in Allentown, said his recent surveys have found Trump running surprisingly well in more affluent suburbs.

"If Trump is even with folks in the suburbs, he's done something to expand his coalition," Borick said.

And that would be important in a general election if he is the Republican nominee. "There just aren't enough blue-collar white voters for him to win," Borick said.

Sanders' best chance of a breakthrough Tuesday appears to be in Connecticut, where Clinton has a relatively narrow lead. Clinton has been trying to shut the door on him by aligning herself with the families of victims of the 2012 Sandy Hook school massacre, as well as other gun control groups.

Sanders voted for legislation to grant gun manufacturers immunity from lawsuits - a decision Clinton has repeatedly criticized. She is betting it has powerful resonance in the Nutmeg State.

The general population is roughly split between support for gun control and for gun rights, including those ages 18 to 29, the prime target of Sanders' campaign, according to a 2015 Pew Research Center survey. But the issue is important to two voter blocs that have backed Clinton to the brink of the nomination: women and African Americans.

Seventeen delegates go to Pennsylvania's statewide GOP presidential winner, but 54 delegates are elected in the congressional districts (three in each), and they are free agents, even from the first ballot.

The takeaway will be who wins the state and gets momentum, but there's a juicy subplot surrounding those unbound delegates. Campaigns are trying to recruit them and keep them loyal - and to advertise the right delegates to their supporters.

Cruz's campaign has fielded a slate of 26 delegate candidates (of the 160 running). Trump claims a team of 41. Many others, however, are aligned with the GOP structure. They say they will support whoever wins the popular vote in their congressional district on the first ballot - but will consider "electability" on subsequent ballots.

Black voters have been key to Clinton's victories elsewhere, and she has campaigned extensively in Philadelphia's African American neighborhoods.

"The key thing to watch is: Are we going to see the high African American turnout numbers we saw with Barack Obama on the ballot?" Borick said. "It may be a bit of a harbinger for the fall, when a high black turnout will be crucial. She's got to clean up, to get Obama-like numbers."

For fun, take a look at the returns from this working-class town outside Pittsburgh proper. It's Ohio Gov. John Kasich's hometown. Will he win there?

tfitzgerald@phillynews.com

215-854-2718

@tomfitzgerald

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