Late last week the campaign in support of Initiative 594 – which would require criminal background checks on gun show and Internet firearm sales if approved this November – launched with a predictable press conference, at least for those familiar with the road map to victory traveled by 2012’s Referendum 74, which legalized same-sex marriage. Prosecutors like King County’s Dan Satterberg (a Republican) and Snohomish County’s Mark Roe (a Democrat, and self-proclaimed “gun guy”) took to the stage, selling the virtues of the initiative. Faith leaders like the Rev. Sandy Brown, whose First United Methodist Church in Seattle played host to the event, where there too, as were plenty of gun-violence survivors. It was just the mix you’d expect from a campaign that will cast I-594 as a widely supported bipartisan effort to bring sensible gun regulations to Washington.

We’ve written about the man guiding the I-594 ship before. Campaign manager Zach Silk – Nick Hanauer’s right-hand man, who, as Nina Shapiro noted earlier this month, scored “the biggest political success of his life leading the campaign to pass the state’s same-sex-marriage initiative,” is hoping for the same success this time around. With a little over seven months to go until voters will decide I-594’s fate, Silk says the biggest challenge will be fending off the sure-to-come onslaught of gun lobby money, while maintaining the support that background checks enjoy in Washington.

Like R-74 before it, much of Silk’s work so far has been in building a broad coalition of supporters for I-594 from all walks of life, hopefully driving home the idea that gun background checks aren’t a partisan issue. So far, Silk says the I-594 campaign has found “natural allies” in the faith communities and among gun-violence victims and survivors. He expects endorsements like those given by Satterberg and Roe to continue.

“The great thing about the campaign we built so far is we’ve built a really broad base of support, and a really big tent,” says Silk, noting that they’ve gathered signatures from every county and legislative district in the state – or, as he puts it, “from Pullman to Sequim, and everyone in between.”

“There is an assumption that this is somehow a blue vs. red issue,” he continues. “But we’ve actually found that not to be the case. … For me, much like it was on marriage equality, we’re not making any assumptions on who is not with us. We believe this is a popular common sense measure. We believe most people will stand with us.”

While there are similarities between the Referendum 74 and I-594 efforts, there are also differences, Silk tells Seattle Weekly.

“The similarities with 74 are that there’s a really well financed, very sophisticated opposition. That was the same with marriage equality across the country,” says Silk. “One thing that is different is we start with incredible popular support. Our task will be to protect that support from eroding when our opposition tries to confuse and scare people.”

Speaking of the opposition, one would be a remiss not to mention the initiative effort that will compete with I-594 this November, I- 591, which is sponsored by Alan Gottlieb of the founder of the Bellevue-based Second Amendment Foundation. I-591 seeks to prevent any state-level gun regulations that haven’t been enacted nationally, and, as the politicking heats up, is sure to benefit from contributions from the gun lobby. So far, according to the Seattle Times, 594 has brought in $1.56 million in donations, “including $315,000 from venture capitalist Nick Hanauer,” while Initiative 591 has raked in $722,000.

According to Silk, his gun background check effort will keep its eye on delivering the 594 message, but will be forced to address the implications of 591 as part of the broader discussion. Silk calls 591 a “cynical attempt to confuse voters.”

“We will be highlight the fact that 591 would actually prevent us from having universal background checks in the state ,” says Silk, a proposition he classifies as “wildly out of step” with the state as a whole.

While recent polling has suggested Washingtonians support the idea of expanded gun background checks – in December, for instance, a statewide poll showed that 74.3 percent of Washington voters support requiring criminal background checks for gun buyers – one need look no further than 1997, and the last time the state voted on a gun-related issue, for notes of caution. As Joel Connelly noted last week, “The state’s last ‘gun election’ was in 1997, over an initiative to require trigger locks on stored firearms and to require that purchasers take a gun safety course. … The measure enjoyed a 65-35 percent lead in early polls, but a saturation campaign by the National Rifle Association sent it down to a thumping defeat.”

At least as the coming battle is concerned, it’s a history that’s likely to repeat itself. “We’re going to hold our ammunition, so to speak, until we’re closer to Election Day,” I-591’s Gottlieb tells the Seattle Times. “We’re marshaling our forces for Election Day.”

“I’m very confident. We start from a much stronger position,” says Silk, in contrast, comparing I-594 to previous the 1997 gun lock effort. “ We have larger, broader base of support. I think we’re in a position where we believe we can be competitive with the gun lobby.”

That’s not to say the challenge is being taken lightly. Silk says the I-594 campaign has already met with Washington Cease Fire, Ralph Fascitelli’s high-profile gun-safety nonprofit, which analyzed the 1997 defeat. Silk says they’ve taken those lessons to heart. “We’re in a position to succeed partially by learning the lessons from 1997,” he says.