Ohio could be Exhibit 1 in the case against gerrymandering, blamed by some analysts for the current standoff in Washington.

True to its reputation as America’s premier purple state, Democratic President Barack Obama won Ohio by 3 percentage points in the 2012 election. Meanwhile, Republicans outpolled Democrats by a slim 51 percent to 49 percent margin in last year’s 16 congressional races.

The outcomes suggest neither party has a strong edge over the other. Yet, the GOP won 75 percent of the congressional seats, taking 12 to the Democrats’ 4. And the average margin of victory in the 16 races was 32 percent.

In Ohio, and many other states where political parties control the process, districts are drawn so safely for incumbents that they have little fear of losing their seats in general elections and instead must protect their flanks in primary elections.

That, say some analysts, has contributed to an ideological tug-of-war where incumbents fear that any compromise will bring on a primary challenge.

And here’s the real dicey part: In Ohio, congressional primaries rarely involve more than 10 percent of a district’s roughly 721,000 constituents and typically attract less than 5 percent. So, if a single action annoys enough of the party base, or enough of the 5 percent who vote in that primary race, an incumbent risks having to seek employment elsewhere.

Larry Sabato, director of the Center for Politics at the University of Virginia, said in today’s Congress there is little incentive to solve problems and much incentive to stand firm on ideology. Where bipartisan coalitions once compromised on landmark legislation to guarantee civil rights and enact Medicare, lawmakers in the current Congress “have nothing in common. Nothing,” Sabato said.

Party control

To most good government advocates — and the party out of power — gerrymandering is a four-letter word.

By dint of controlling the Ohio General Assembly, the GOP controlled the drawing of new congressional districts after the 2010 Census. In the 12 districts specifically carved out for Republicans, the average margin of victory was 23 percentage points. The Republicans then drew safe Democratic districts — essentially sacrificing a few congressional seats in order to keep those Democrats from wreaking havoc in Republican districts. The four Democrats won with an average of 59 percent of the vote.

“All of the Ohio seats are safe,” said Paul Beck, an Ohio State University political scientist. “The Republicans would have made theirs even safer except that they wanted to win most of the districts, so they had to shave their projected vote margins a bit and concentrate the Democrats in those four districts.”

When one party gerrymanders to get a disproportionate number of House seats, “you get a disconnect between the values of voters and the values of the people who represent them,” said Ann Henkener, redistricting specialist for the League of Women Voters of Ohio.

“The normal voter is toward the middle of the bell curve,” she said. “They are the people who want compromises, but the whole middle ground has been lost” in Congress.

Secretary of State Jon Husted, a Republican who supports reforming Ohio’s redistricting process, drew a correlation between gerrymandered districts and the impasse on the government shutdown.

“It’s pretty easy to understand,” he said. “If you win your district by 3 percentage points, you receive a very different message from voters than if you win by 30 percentage points…As long as you satisfy the 5 percent of voters who vote in primaries, that’s essentially who’s commanding your attention. The only thing that a member of Congress has to fear is a primary, not a general election, so that means loyalty to party and loyalty to ideology are the most important things to get re-elected.”

Other variables

David Wasserman of the Washington-based Cook Political Report said gerrymandering isn’t the only explanation for Washington’s polarization. Over the last 20 years, he said, people have increasingly self-sorted themselves by political ideology, with cities becoming bluer and rural and suburban voters becoming redder. Most American voters in 2012 lived in counties that gave either party’s candidate at least 60 percent of the vote.

“I don’t think redistricting is the chief explanatory variable here,” Wasserman said.

A new analysis by Cook shows that 2012 marked only the second time in the last 70 years that one party — in this case, the Republicans — won a majority of the seats in the U.S. House while receiving a minority of overall votes.

During the last government shutdown in 1995 and 1996, some 79 Republicans represented districts that Democrat Bill Clinton had carried in 1992. Today, only 17 Republican-held districts were won by President Obama. That means 79 House members had to worry about losing a general election in 1996, compared to 17 today.

Norman J. Ornstein, a political scientist and resident scholar at the American Enterprise Institute, a conservative Washington, D.C., think tank, says America’s neighborhoods are becoming less politically diverse. He calls it “the big sort.” People are increasingly moving to areas where they are surrounded by like-minded people, meaning those elected to represent them don’t necessarily have varying interests to represent.

“It’s not just that a Republican in a homogenous district fears a primary,” he said. “They fear a primary that gets $3 million thrown in from the Club for Growth against them, that they’ll have Heritage Action mobilizing and using social media against them, (and) that someone can jump in and put millions anonymously against them.”