The images out of Washington state toward the end of 2012 — all-night parties celebrating legalized pot and same-sex marriage — sparked hope among liberal activists that the tide has turned on these two issues.

Even though national polls show more openness to pot and gay marriage nationwide, it raised the question — why Washington?

Oregon, the state’s blue neighbor to the south, has not successfully mounted campaigns to approve pot or same-sex marriage. California has had a messy relationship with both issues, and Idaho swings solidly right.

There are a number of unique factors that made Washington ripe for these liberal reforms, experts say.

"There’s a libertarian streak in Washington, and there are more atheists. Religion is part of this," University of Washington Professor John Findlay told NBC News. The state is one of the least religious, with only about half of Washingtonians telling the Gallup poll in 2008 that religion plays a part in their daily lives.

Beyond pot and same-sex marriage, Washington also allows physician-assisted suicide (as do Oregon and Montana) and was one of four states that decriminalized abortion before Roe v. Wade in 1971. To top off its liberal cred: A Democrat has been in the governor's office since 1980 — longer than any other state.

Cliff Despeaux / Reuters Washingtonians light up near the Space Needle in Seattle after the law legalizing the recreational use of marijuana went into effect in the state.

But to describe Washington as a purely liberal state is to oversimplify its politics. Outside of the Puget Sound area, Washingtonians have more in common with Red State residents than they do coffee-craving Seattleites.

"Without Seattle, we’d be Idaho," says pollster H. Stuart Elway. Seattle-area voters accounted for one-third of the state total.

Washington has no income tax, and the possibility of implementing one is rarely mentioned, even during tough economic times; in 1998, voters nixed affirmative action; two years later, they approved $30 license plate tab renewals, a dramatic fee reduction that cut into city and state coffers, hiking up bus fares and leaving potholes unfilled.

What ties all these measures together, beyond a "live and let live" ethos, is the state's initiative and referendum process, which gives voters, not lawmakers, the power to set policy much more directly than in other states.

Findlay says the initiative process can be traced back to the state’s early days, when Washingtonians, buoyed by the progressive and populist movements, didn't trust their politicians. While politicians in most other states manage what goes on the ballot, Washingtonians can pay $5 to submit an initiative or referendum. Get 241,153 valid signatures (120,557 for a referendum) and that measure is inked on the ballot.

"There’s a legacy of distrust of the Legislature stemming from 100 years ago that has continued to shape politics for more than a century," Findlay said.

Although 24 states and the District of Columbia have an initiative process, it has been most used by the Western states, particularly California, Oregon and Washington, making them laboratories for special interest groups.

Take marijuana, for example, where outside money was a big part of the campaign. Drug Policy Action in New York fronted $1.6 million; Progressive Insurance CEO Peter Lewis, who supports drug reform and lives in Ohio, donated about $2 million.

Elaine Thompson / AP King County Executive Dow Constantine, right, embraces Pete-e Petersen as her partner, Jane Abbott Lighty, watches after Constantine issued the the county's first marriage license to a same-sex couple. On the night that same-sex marriage became legal in Washington state, many of the state's issued marriage licenses beginning at midnight.

Given their success in Washington and Colorado, Drug Policy Action is looking to push similar campaigns in California and Oregon in 2014 or 2016. Both states have legalized medical marijuana and in California, medical pot has becoming a booming business since it was approved in 1996. A 2007 federal study estimated that Californians consume one million pounds of pot a year.

"We have these results in Colorado and Washington under our belt, so that sort of fertilizes the ground," Dale Gieringer, who heads the California office of the National Organization for the Reform of Marijuana Laws, told Reuters.

Outside money also played a role in the battle over gay marriage, but so too did some Washington billionaires, including Bill Gates, co-founder of Microsoft, and Jeff Bezos, founder of Amazon, who collectively gave more than $3 million to the campaign to approve same-sex marriage.

"The populist and progressive movements are over, and the feelings are over, but there’s this tool," Findlay said. "A lot of us complain about those things, but it doesn't matter, because it’s going to shape politics in this state. This is the tool we have that most other states don’t have. It’s part of how we do things here. And it doesn't work exclusively for progressives or conservatives."

Other reasons floated for the state’s unique positions on issues: Unions have long had a stronghold in the state, as have female politicians -- the state was home to Dixie Lee Ray, the fiery former governor whose motto during her 1976 campaign was “Little lady takes on big boys.”

But, as Elway noted, Washington’s votes often come down to the Seattle area. Elsewhere on Election Day, conservative Washingtonians watch in dismay as their leads are turned upside down as results from the metropolitan area trickle in.

State Republican Party Chairman Kirby Wilbur told the Seattle Times that the votes speak for themselves.

"Washington has always been a socially liberal and economically conservative state," he said.

To be fair, Washington may not be so far ahead of the rest of the country on social issues such as pot and same-sex marriage, according to Mark Smith, who teaches political science at the University of Washington.

Smith noted that 53.7 percent of Washingtonians approved same-sex marriage. Polling figures show a similar, if slightly lower, level of support nationwide.

"We’re not that far ahead of the nation,” Smith said. "The whole nation is trending; we’re just further along than the rest of the country."

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