The Orange County Registrar's Office of Voters released new numbers showing 547,458 registered Democrats in the county, compared to 547,369 Republicans.
Democratic leaders say the shift is thanks to demographic changes, aggressive recruitment efforts and opposition to President Donald Trump.
Republican leaders attribute it to conservatives moving out of the state because of the cost of living, and the increase in voters with no party preference. Voters who are not aligned with a political party have climbed to 440,770, according to the registrar's office.
Democrats edging out Republicans is monumental for an area with a reputation for being a GOP hotbed and the home of President Richard Nixon.
"As the Latino population has grown and as the rhetoric against them has become increasingly harsher, they've moved increasing numbers over to the Democratic Party. Reagan of course did very young with latinos, but the young and people of color sense that the Republican Party is not for them," said Fred Smoller, an Associate Professor of Political Science at Chapman University.
It's a shift in voting patterns that didn't happen over night. Back in 1988, 31 years ago, 55% of registered voters in Orange County were Republican, 34% were Democrats, and 8.5% were unaffiliated. Today, Democrats are slightly ahead by roughly 89 registered voters and that number is expected to go up. Another number On the rise, no party preference - which makes up 27% today.
Chapman University Professor Fred Smoller points to changing demographics in the county and how conservative white male voters make up less of the electorate.
"They're being replaced by younger voters who do not get upset by people's sexuality. Get much more comfortable with diversity and are very concerned with climate change and gun control," said Smoller.
In a statement, Orange County Republic Party Chairman Fred Whitaker said in part that the "county is still a conservative county but it's now a purple county. It's now a fight for the No Party Preference voters who have grown exponentially throughout the state recently and Orange County isn't immune to that trend." But OC Democrats point to President Trump.
"People don't feel that their president represents them and that's why we have 20 presidential candidates on the dem side because we want to find the right person to lead our country forward. Especially in Orange County that has three million people, we're larger than 22 other states," said LuisAndres Perez, the Political Director for the Orange County Democratic Party.
Political Scientists say what's happened in Orange County is a preview of what they're seeing in counties in states like Texas and Ohio, States that could decide the 2020 presidential election.
Four congressional seats were flipped in last year's midterm, sealing Orange County's complete shift to blue.
Katie Porter captured the 45th congressional district in the county, becoming the first Democrat to hold office there.
She attributed the change in many long-time Republican districts in favor of Democrats to some of President Trump's statements and actions.
"We ran a campaign that was about listening to people, that was about listening to their concerns," Porter said following the 2018 midterms. "Some of those concerns included things the president is doing, things that Rep. Mimi Walters supported."
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