There are a growing number of social scientists who have looked at election results in Pennsylvania over the last six years and concluded we are a national poster child for partisan gerrymandering.

Gerrymandering -- drawing political boundaries to give one political party an edge -- has been blamed for declining competition at the polls, decreasing voter interest and increasing partisan gridlock in the halls of government.

It's lit a fledgling reform effort aimed at trying, both in the state courts and in the Legislature, to change the way Pennsylvania redraws its legislative districts every 10 years.

But if Pennsylvanians are being real about the current state of our electoral politics, gerrymandering isn't the only reason for the current lopsided GOP majorities in the its state House, Senate and congressional delegation.

It's clear that, from a tactical standpoint, one side has simply been playing the game of legislative politics better than the other.

Want evidence?

In the 50-seat Pennsylvania state Senate right now, there are 18 districts where a majority of registered voters are Democrats, and eight more where Democrats outnumber Republicans.

But Republicans hold 10 of those seats.

By contrast, Democrats hold zero of the 24 districts where registered Republicans outnumber Democrats.

It's very similar in the state House of Representatives.

Republicans hold voter registration edges in 99 districts; Democrats have captured three of them. But Democrats have ceded to seats to Republicans in 25 of the 104 districts where, on paper, they should have an edge.

State Representatives are seated before the taking the oath of office during swearing-in ceremonies. The ceremony marked the convening of the 201st legislative session of the General Assembly of Pennsylvania.Dan Gleiter | dgleiter@pennlive.com

The Pennsylvania Congressional delegation? Same story.

Each party holds voter registrations edges in nine districts.

The GOP holds all of its seats, several of them in districts that have been shaped and reshaped until they look like that they have been run through a taffy-pulling machine.

Democrats, meanwhile, have lost four seats in districts where they currently have pluralities.

In interviews with Pennsylvania political strategists, former candidates and scholars, we get a series of explanations why -- aside from the dreaded gerrymander -- the battlefield has tilted as far as it has.

The cult of personality.

In the modern age, when candidates at the top of the ticket are named Ed Rendell, Barack Obama, or Robert P. Casey (Sr. and Jr.), Democrats often find themselves in fat city, able to run up large statewide victories.

But that has rarely translated into party-building at the local level - where candidates can be developed, groomed and recruited for legislative seats.

The examples are boundless.

Rendell did bring home a small Democratic majority in the state House when he won re-election as governor in 2006, but it was washed away by huge GOP wins in the Tea Party-inspired 2010 cycle.

Even as Democrat Tom Wolf scored an historic, cycle-breaking statewide win over unpopular Republican incumbent Gov. Tom Corbett in 2014, his party allies in the state House saw their caucus shrink back from 91 seats to 84.

Even as Tom Wolf won the governorship, he saw the number of Democrats in the state House decrease. Sean Simmers, PennLive.com. January 20, 2015

Last year, Democrat Hillary Rodham Clinton actually rolled up slightly bigger presidential vote margins in the Philly suburbs over Republican Donald Trump than Obama posted in 2012 over Mitt Romney.

But for all that, the Democrats only flipped one state House seat in the region, West Chester Mayor Carolyn Comitta's 25-vote squeaker over incumbent Republican Rep. Dan Truitt. That was more then off-set by their loss of three more seats in the shifting Southwest.

One reason may be that Republicans simply play a better ground game, from filling local party committee seats, to candidate recruitment (Democrats had no one on the ballot in 51 of 203 state House seats last year) to getting voters to turn out for every election.

"Republicans have just been better at those aspects of the political game in Pennsylvania for a long time," said Christopher Borick, a political science professor at Muhlenberg College.

Democratic leaders reached for this story agreed, though they were reluctant to speak publicly because they didn't want to criticize friends and allies in the press. But whether it's Wolf's political team, legislative leaders, allies in organized labor or county organizations, no one appears to have led a cohesive effort to win back legislative seats.

A lack of geographical diversity.

This has led to GOP domination in county courthouses, town halls, and township supervisor offices across Pennsylvania -- the traditional breeding ground for state-level candidates.

It's always been true that the GOP has dominated for decades in vast regions of Central Pennsylvania, and Congressional races there really wouldn't be competitive no matter how the lines were drawn.

But did you know that right now 54 county courthouses are powered by Republican majorities in the county commissioner or council offices? The Democrats have 13.

Counties are political sub-divisions, like states. They can't be gerrymandered.

You know those vote-result maps from the last few election cycles that portray America as blue coastlines bordering a sea of mostly red land-mass in between?

Something similar is up in Pennsylvania, as the Democratic Party -- historically the home for racial minorities, gay voters, union members, Catholics and Jews, and the descendants of our immigrant ancestors -- has increasingly seemed to back itself into geographical corners. Namely Pittsburgh and Philadelphia.

Of course, there are still some serious swing areas out there: The Philly suburbs, the Lehigh Valley and, to a certain extent, the northeastern end of the state.

But it's getting increasingly hard to find enough practicing Democrats to elect members to the state legislature from the 717 (South Central) or 814 (North Central) or 724 (Southwest) area codes.

That's especially true outside of the small cities in those areas -- Erie, Harrisburg, Johnstown, Lancaster or York.

The state Senate provides the starkest example. Aside from three seats covering parts of the heavily Democratic city of Pittsburgh, the Democrats now hold no state Senate seats west of the Susquehanna River.

This may have something to do with...

Losing the message battle.

This may be the biggest problem of all for the Democratic Party.

Democratic voters in many parts of the state -- especially in southwestern Pennsylvania counties like Westmoreland, Washington, Beaver, Greene and Fayette -- are often Democrats in name only.

This started with the phenomenon of Reagan Democrats 30 years ago: White, working-class voters who saw a Democratic Party nationally that they felt wasn't prioritizing their concerns anymore.

"Government did not come to their rescue when the place went to hell in a handbasket. When the manufacturers just picked up and left, they knew it, and they started voting the other way," said Joseph DiSarro, chairman of the political science department at Washington & Jefferson University and, full disclosure, a member of the Pennsylvania Republican State Committee.

What's happened in the generation since has largely reinforced those trends, DiSarro said.

Steel- and coal-driven economies have been replaced by the new hope, natural gas, and many of those same voters see the Republicans as the party that can best build a new energy economy in Pennsylvania.

"We have moved from being the Rust Belt to a pro-business, pro-energy area and they don't want to see regulation from Washington D.C. or Harrisburg," DiSarro said. "This has come to fruition over time, and I think the Democrats are going to have a very difficult road ahead of them to rebuild their strength out here."

The message problem, other lifelong Pennsylvania Democrats say, is only amplified by the age of nationally-televised punditry that presents liberals like Sens. Bernie Sanders and Elizabeth Warren as the party's national face.

That's not a rallying point for western Pennsylvania's Democrats, many of whom are easily as conservative as any Republican in the Philly suburbs, said former state House staffer-turned-lobbyist Mike Manzo.

It's in part what GOP candidates like Lou Barletta, who has announced plans to challenge incumbent U.S. Sen. Robert P. Casey Jr. next year, are banking on.

"The national Democratic brand is very liberal, and obviously that showed in the presidential election," agreed Philadelphia public relations executive Larry Ceisler, a former Democratic strategist

Has Republicanism peaked?

Despite all of above factors, most political scientists believe gerrymandering has been a real, and even a major factor in weird election results of the of the past several years.

It's just that it's not the only factor.

"Republicans have been able to tip the scale with gerrymandering," Borick said. "But they've been able to push the scale even more with their stronger party structure and campaign strategy.

"Put those things together, and you get the math we've seen in recent elections."

All of which raises this question: Have we reached "Peak Republicanism" in Pennsylvania?

If there's a consolation prize for Democrats, it appears likely that the political maps can't get much worse for them after 2020.

Any shift in seats due to population changes is likely to be from West to East, and it is in the east where the Democrats have been most competitive in recent cycles.

If Wolf wins a second term as governor, the requirement of his signature on the bill defining the new Congressional lines should have a moderating effect on those maps. Then too, the Pennsylvania Supreme Court -- which would hear appeals -- is likely to have a solid Democratic majority for years to come.

But as we've seen over the last few cycles, nothing is guaranteed in politics. Whether any of this translates into different results at the polls, well, that will be up the candidates and their campaigns.