Washington (CNN) Democrats see Ralph Northam's big win in the Virginia governor's race as a breakthrough moment for the left's digital efforts.

A year after Republicans leapfrogged the Democrats' digital capacities on the way to President Donald Trump's election, progressive groups combined spent nearly $3 million on an innovative effort to modernize the party's digital advertising.

The effort, organized by Planned Parenthood and coordinated by veteran Democratic digital strategist Tara McGowan, reached 2.4 million Virginia voters without Northam's campaign having to spend any money at all on digital advertising.

"It wasn't just talking, sharing what plans were -- it was really the nitty-gritty details of putting together a program we all felt really good about," said McGowan, the head of the new digital firm ACRONYM.

Coordination is standard in politics when several outside groups are working to aid the same candidate. But Virginia's laws allow campaigns and outside organizations to share plans and strategies -- which opened the door for what became the Democratic Party's best-coordinated joint digital effort yet.

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