Craig Gilbert

Milwaukee Journal Sentinel

The USA TODAY Network spent time in eight counties in eight states this fall, exploring the key electoral themes that could decide the election. The series looked at Waukesha County in Wisconsin, Chester County in Pennsylvania, Wayne County in Michigan, Maricopa County​ in Arizona, Union County in Iowa, Larimer County in Colorado, Clark County in Ohio and Hillsborough County in Florida.

America’s next president will be the product of a contest with no parallel in modern times.

It has featured the most unpopular nominees in polling history, the nastiest debates in decades, late-breaking bombshells, a Republican “civil war,” surprising shifts in the election map and the newest fault line in American politics: the “education gap” between Trump and Clinton voters.

To explore the impact, the USA TODAY Network spent time in recent weeks with voters in eight counties around the country, selected because they illustrate key electoral themes of the 2016 campaign.

In this final story before the election, we revisit these counties and examine what clues they offer about next Tuesday.

This iconic GOP stronghold in the Milwaukee suburbs has never quite warmed to Donald Trump, highlighting one of his biggest obstacles against Hillary Clinton.

For much of this race, the Democratic nominee has been getting more support from her party’s voters (just under 90% nationally) than he has from his (just over 80%).

That “loyalty gap” has accounted for most of Clinton’s lead this fall.

When we talked to habitual Republicans in Waukesha, Wisconsin’s third-largest county, we found widespread qualms about Trump’s temperament, political depth and conservatism. In a place where Clinton is intensely unpopular, that has left many voters pained and conflicted.

It also has left Trump with a much smaller edge in this landslide county than his party typically enjoys. That’s a stark reversal of form, since Waukesha has been growing more Republican (compared to the rest of the country) with every presidential race for 40 years.

Trump’s weakness in the GOP’s high-turnout suburban base has offset his strength in more rural and blue-collar parts of Wisconsin, and it’s complicated his dogged push to “flip” a state that has voted Democratic for president seven times in a row.

National polls are now showing some signs of Republican voters “coming home” to their nominee, a trend that could be boosted by a revival of the Clinton email controversy. That is essential for Trump.

One election night key to watch: whether Trump gets the huge margins and turnouts his party needs from reliably red suburbs in metropolitan battlegrounds like Milwaukee, Charlotte and Cincinnati.

Republicans have won over white college graduates in every presidential race since 1956.

That streak may end next week, thanks to an education gap that has become the demographic hallmark of the Clinton-Trump election.

No group has swung more sharply toward Democrats since the last presidential race than white college-educated women. They voted Republican four years ago but now favor Clinton by large margins, a trend exacerbated by the recording of Trump’s sexual boasting and allegations about his behavior toward women.

The fallout is being felt in such suburban battlegrounds as Northern Virginia, North Carolina’s Research Triangle and the Philadelphia suburbs, where we spoke with many voters — even those mistrustful of Clinton — who were dismayed by Trump’s tone and rhetoric.

Chester County has the highest share of college-educated adults in Pennsylvania. Unlike Waukesha, it has been growing less Republican over time, not more — a trend in many white-collar suburbs that ring large cities.

Chester was decided by less than a point in 2012. But a recent Pennsylvania poll by Bloomberg Politics showed Clinton with a 28-point lead in Philadelphia’s suburban counties, home to almost 3 million people. That represents another high hurdle in Trump’s effort to turn a blue state red.

One election night key to watch: whether Clinton does better than Obama did in purple, high-education counties like Jefferson, Colo. (outside Denver), Loudoun, Va. (outside Washington, D.C.) and Wake, N.C. (home to Raleigh).

Four years ago, 38 precincts in Detroit cast zero votes for the Republican presidential ticket.

Trump has pointed to big-city returns like those to argue the elections are “rigged.”

But the pattern is easily explained by a familiar feature of presidential politics: African-American support for Democrats is one-sided in the extreme.

President Obama won 93% of the black vote, according to 2012 exit polls. He won 100% in some precincts in Milwaukee, Philadelphia, Chicago and other cities. He won 98% of the vote in Wayne County’s biggest city, Detroit. In a recent Detroit Free Press/WXYZ-TV poll, no black voters in the survey backed Trump.

The Republican has tried to woo African-American voters, even taking his pitch to a Detroit church this fall. But it’s clear here and elsewhere that his message has been undercut by his own rhetoric, including his claims of urban voting fraud and his bleak portrayal of black communities as violent and despairing.

Clinton faces a very different challenge when it comes to her party’s most lopsided supporters: maximizing their vote in battlegrounds like Michigan, North Carolina, Ohio and Florida.

There is no group where the rise and fall in turnout has a more direct impact on elections because its vote goes almost entirely to one side. But Clinton doesn't generate the enthusiasm Obama did. In the president’s re-election, black turnout surpassed white turnout, according to census surveys.

That’s a campaign feat Clinton may have trouble replicating.

One election night key to watch: whether Clinton gets fewer votes than Obama in counties with sizable black populations such as Philadelphia, Milwaukee and Cuyahoga, Ohio (Cleveland).

Arizona was not expected to be a tossup state in 2016, having voted Republican for president in every election but one since the 1960s.

But right now it’s more competitive than some perennial swing states, inviting a late Clinton ad blitz.

One big reason: a Latino backlash against Trump’s hard line on immigration and his comments about Mexican-Americans. Something similar has happened in Texas, where the Republican margin is far slimmer than in previous races.

Polls give Clinton a more than 2-to-1 lead among Latinos in Arizona.

Once again, turnout is the x-factor. Four years ago, Latinos made up 30% of the population in massive Maricopa County (home to Phoenix), but only an estimated 15% of the votes cast. Latinos have lower rates of citizenship and lower rates of voting, diluting their political clout.

Maricopa County hasn’t voted Democratic in more than 60 years.

But if that streak ends this year, it could alter the presidential map.

One election night key to watch: whether Latinos match the share of the total vote they represented in the 2012 national exit poll (10%) and in critical states like Florida (17%), Nevada (19%) and Arizona (18%).

Iowa has been one of Trump’s best and Clinton’s shakiest battlegrounds, despite having twice voted for Obama.

A key factor is Clinton’s weakness and Trump’s strength with rural voters, who made up more than half the vote in Iowa in 2012, far higher than in any other swing state. Democrats need to be competitive with rural whites to win battlegrounds like Iowa, Wisconsin and New Hampshire.

In Iowa’s Union County, home to fewer than 13,000 people, many voters we talked to pointed to the economic struggles of rural communities to explain the appeal of Trump’s populist message.

Those communities also match the demographic profile of Trump’s core support: older white voters without college degrees.

The divide between urban and rural voters has been a growing feature of American politics, and the Trump-Clinton contest has widened it. Obama won urban voters by 26 points and lost rural voters by 20, according to the 2012 exit poll — a gap of 46 points.

That gap could grow even larger this year.

One election night key to watch: whether Trump exceeds Mitt Romney’s 2012 share of the rural vote in Wisconsin (53%), Iowa (52%) and Ohio (60%).

Young voters have no perceived champion in this race: Obama is off the ballot and Democrat Bernie Sanders lost his party’s nomination.

Clinton has struggled to mobilize and inspire them.

Colorado is the youngest state (demographically) of the battlegrounds. And very purple Larimer County, home to Colorado State, is among its younger counties.

Young voters here and elsewhere have been slow to embrace either nominee, raising questions about how many will stay home or vote third party.

No part of the “Obama Coalition” has been softer for Clinton, whose relationship with millennials has been a “complicated” one, according to John Della Volpe, a pollster for Harvard’s Institute of Politics.

He found some signs of progress for her in a national poll Harvard released last week. Clinton easily led Trump 49% to 21% among voters 18 to 29.

But that left almost a third of young voters preferring a third-party candidate (14% for Libertarian Gary Johnson and 5% for the Green Party’s Jill Stein) or undecided (11%).

While views of Clinton had improved after the July conventions, they were still more negative than positive among young voters.

One election night key to watch: whether the under-30 vote matches its share of the national vote in 2012 (19%) and whether Clinton wins those voters by a margin similar to Obama’s (23 points).

Of the five battleground states where blue-collar whites are a majority of the electorate, Ohio is easily the most important in deciding the next president (the others are Wisconsin, Michigan, Iowa and New Hampshire).

When we visited Clark County, home of Springfield, we found a community striving to bounce back from years of harsh industrial decline.

To the east, Youngstown, Ohio, has become a national symbol of Trump’s Rust Belt, working-class appeal to struggling whites who may have once voted Democratic.

But the story in Clark County is more mixed, as voters struggle with their qualms about both candidates. Trump’s stands on trade and immigration appeal to some, while his volatility turns off others.

Clark County was decided by 523 votes in 2012 and is expected to be closely divided in this election.

In an Ohio poll by NBC/Marist last month, Trump trailed Clinton by 12 points among college grads but led Clinton by 10 points among non-college educated voters.

Blue-collar whites (Trump’s base) historically vote at lower rates than college-educated whites, who lean toward Clinton this year.

Closing that turnout gap is an obvious challenge for Trump. But it is also an opportunity, since turnout among blue-collar voters has more room to grow.

One election night key to watch: just how big the divide is between college and non-college voters (in 2012, there was virtually no difference in the way the two groups voted).

This county, home to Tampa, is the quintessential battleground within a battleground — a big, diverse and purple region in a diverse and massive swing state.

Because Republicans have lost ground elsewhere on the map, there is no path to victory for Trump without Florida’s 29 electoral votes.

Hillsborough County is a microcosm of the nation in many ways: urban, suburban, rural; 51% white, 27% Hispanic and 18% black. It features all the dividing lines that have marked this contest: race, gender, education and age. And it has picked the winner in 19 of the past 20 presidential elections.

But while the region is a cross-section of America, the Tampa-St. Petersburg area has a distinctive place politically among the nation’s major metropolitan areas, which have been trending Democratic over time, boosting the party’s vote totals.

Obama won 35 of the 50 most populous metros in 2012 — by a staggering margin of almost 12 million votes.

Only 15 of the top 50 metros voted Republican, most of them in solid red states.

But metropolitan Tampa Bay mirrored the national vote more closely than almost any other large metro four years ago. It is arguably America’s top battleground-state battleground.

We found signs that both Clinton and Trump were struggling to solidify their political bases of support here, reflecting a contest that has largely pitted one candidate’s “negatives” against the other’s.

Hillsborough County will be critical next Tuesday in the battle for America’s top electoral prize.

And in that sense, it will help determine whether Trump’s path to the White House is merely difficult, or impossibly narrow.

One election night key to watch: if Trump loses Florida, his hopes are dead and all suspense about the outcome will be over; if he wins Florida, he'll still need to win Ohio and probably Pennsylvania to have a chance.

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