Craig Gilbert

Milwaukee Journal Sentinel

Having Donald Trump in the White House has had a revolutionary effect on the economic outlook of Wisconsin’s most partisan voters, recent polling suggests.

In a flash, it has turned Republicans into rosy optimists and Democrats into dour pessimists, reversing the mood of voters in both parties.

You probably didn’t need a poll to tell you that.

But the polling also tells us something more stark and fundamental about the partisan prism through which many voters see the world.

Trump’s election did more than change the expectations of Republicans and Democrats about the economy’s future performance.

It altered their assessments of the economy’s actual performance.

When GOP voters in Wisconsin were asked last October whether the economy had gotten better or worse “over the past year,” they said “worse’’ — by a margin of 28 points.

But when they were asked the very same question last month, they said “better” — by a margin of 54 points.

That’s a net swing of 82 percentage points between late October 2016 and mid-March 2017.

What changed so radically in those four and a half months?

The economy didn’t. But the political landscape did.

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Republican Trump replaced Democrat Barack Obama as president. With their own party now in power, Republicans overwhelmingly upgraded their evaluations of America’s economic performance.

“That’s a testament to the power of partisanship to rewrite our perceptions, even when the objective reality has hardly changed,” says the Marquette University Law School’s Charles Franklin, who conducted the polls cited above.

Something similar has happened in the nation as a whole. As the New York Times reported recently, Republicans and Democrats have done an about-face since the election in their economic outlook, with the partisan gap in national consumer sentiment bigger than ever before.

The Wisconsin polling is a striking illustration. Asked last month if, “looking ahead,” they expect the economy to get better, worse or stay the same over the next year, GOP voters chose “better” over “worse” by a margin of 80 points. Democratic voters chose “worse” over “better “ by a margin of 43 points.

That is the biggest partisan gap Marquette has ever recorded on this question in 42 polls dating back to the beginning of 2012. And it represents a huge shift since last fall for voters in both parties.

But the Wisconsin polling adds some other wrinkles to this story.

In its polls, Marquette poses a second question on the economy, asking voters to rate its performance over the past year.

Across more than five years of Wisconsin surveys, the results show some very distinctive patterns.

One is that the Republicans have shifted more dramatically in their views of the economy than Democrats, from overwhelmingly negative during much of the Obama presidency to overwhelmingly positive with Trump now in the White House. Democrats’ assessments of the economy darkened after Trump’s election, but the shifts in their views have been much more modest.

Two, the economic perceptions of both Republicans and Democrats have routinely seesawed with the state’s election cycles.

In presidential campaign seasons, Democratic voters have given the economy their best grades, Republicans their worst grades. Why?

One explanation is that the run-up to an election is when partisan voters are most likely to see the economy through a partisan lens. With Democrat Obama in the White House and his economic record a key campaign issue, his supporters see the economy in the best possible light, his opponents in the worst possible light.

In late October of 2012 — on the cusp of the presidential election — 59% of Wisconsin Democrats said the economy had gotten better over the previous 12 months. That is the highest figure recorded in 42 Marquette polls over five-plus years.

In the same survey, only 5% of GOP voters said the economy had gotten better. That is the lowest figure ever recorded by Marquette.

But just the opposite was true during the state's campaigns for governor, with Wisconsin Democrats giving the economy their worst grades, Republicans their best.

For example, Democratic views of the economy worsened during the recall election over Gov. Scott Walker in the summer of 2012, improved during the fall 2012 presidential campaign, worsened during the 2014 race for governor, and improved again during the 2016 presidential campaign.

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GOP perceptions moved in the reverse direction.

Why would elections for governor produce a different pattern in Wisconsin than elections for president?

One fundamental difference is that in the 2012 and 2014 races for governor, the politician whose record in office was under scrutiny was a Republican — Walker. As a result, both parties adopted an entirely different economic message than the one they had during the most recent two presidential campaigns.

Walker aggressively touted the state’s economic performance under his leadership, while Democrats attacked it. The result? Republican voters grew more positive about the economy and Democrats grew more negative.

In fact, the best grades Republicans have ever given the economy in Marquette’s more than five years of polling were on the eve of the 2014 election, when Walker was seeking a second term. That was also when Wisconsin Democrats gave the economy their very worst grades in 42 Marquette polls.

In short, Democrats and especially Republicans in Wisconsin have changed their views of the economy far more than actual economic conditions have changed. And those views have shifted in concert with the election cycles.

The polling suggests that many partisan voters look to their preferred candidates for cues about how to view the economy, says Franklin, “which shows how much even economic reality is filtered through our subjective perceptions” by voters’ own partisan leanings.