WASHINGTON – Gay marriage wouldn’t have passed in the Washington state Legislature this year without Gov. Chris Gregoire’s decision to reverse course and push for it. Legislators’ personal pleas to colleagues, as epitomized by Republican Rep. Maureen Walsh’s passionate floor speech about her desire to throw her daughter a wedding someday, also played a major role. The speech went viral on YouTube.

But according to the bill’s sponsor, Democratic state Sen. Ed Murray, there was nothing more crucial to the legalization of gay marriage than support from high-profile businesses such as Nike Inc. and Microsoft Corp. “It’s how we got moderate Republicans and conservative Democrats to vote for this,” he said.

Murray and others first harnessed support from the business community for gay rights in 2006 by using an economic development argument to pass an anti-discrimination bill that had been in the works for 29 years. Support from Boeing Co. and Microsoft helped turn key votes.

Since that time, gay rights activists have built aggressively from their original base of industry support. Those efforts culminated in more than 100 businesses publicly supporting gay marriage in Washington state before the bill’s passage in February, from heavy-hitting corporations such as Starbucks Corp., Google Inc. and Alcoa Inc. to mom-and-pop shops scattered around the state. Small business support was key to turning individual legislators, who “know their local businesses,” Murray said.

Support from businesses has also been important in other states that have debated gay marriage, including New York, which voted to legalize it in 2011, and Maryland, which, like Washington, legalized gay marriage in February but faces a referendum effort to put the issue before voters.

The driving force behind business involvement has less to do with the money that gay people might spend in the state than with work force concerns. As more states move toward legalizing gay marriage, more businesses fear being left behind in places seen as backward by gay workers and other young employees who feel strongly about the issue.

“If you’re sending a signal to the world that you’re biased, it doesn’t just scare away gay people,” said Stephen Dull, vice president for strategy and innovation at the North Carolina-based VF Corp., a Fortune 500 company. “It scares away everyone.”

North Carolina voters will consider on May 8 whether to put the state’s existing ban on gay marriage in the state constitution. If that happens, Dull says, it will be even tougher than it already is to recruit the mobile, metropolitan, high-level employees the company is looking to attract for its Greensboro headquarters. VF is the parent company to a host of high-profile fashion brands, including The North Face, Nautica, Lee and Lucy.

Dull says he already has to reassure many of his potential recruits that they wouldn’t be moving to a place that is straight out of the rural South of a generation ago. “If this were going on when I was recruited, I don’t think I could have joined,” Dull said. “It’s not that we’re trying to recruit gay talent, but people see it as a sign of how welcome their ideas will be, no matter how different. And that’s important for innovation.”