Democrats won big in 2017 against Trump and GOP and we're not done yet: Tom Perez We didn’t just focus on the sexy races. We lifted Democrats up and down the ticket with money and organizing, and there's more to come in 2018.

Tom Perez | Opinion contributor

When I was elected chair of the Democratic National Committee a year ago, President Trump responded the way he always does: on Twitter, mocking me and my fellow Democrats. In response, deputy DNC chair Keith Ellison and I made a promise: we would unite Democrats across the country to become his worst nightmare. And we did — by winning some of the biggest races in 2017.

It wasn’t easy and it didn’t happen overnight. In less than a year, we got back to basics and started organizing. We invested in our state parties almost immediately through our Resistance Summer program and hired organizers in over 40 states. We made unprecedented investments in our state parties through our Every ZIP Code Counts program; now each state party gets $10,000 per month, which is a 33% increase from base funding levels in 2016 and a 100% increase from 2015.

And we didn’t stop there. We made an unprecedented investment in local organizing by establishing a $10 million State Party Innovation Fund. We’ve already announced the first wave of grants, totaling nearly $1 million, and we will announce more in 2018 as states organize for critical races.

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In 2017, we went all-in in Virginia, investing $1.5 million to help Ralph Northam, Justin Fairfax, Mark Herring, and Democrats up and down the ballot. We beat Ed Gillespie by a whopping 9 points and flipped 15 state legislative seats, including the first two Latinas and the first openly transgender person elected to the Virginia State House. But we didn’t just invest — we invested the right way. Not one cent went to television ads. Instead, we put all of our time and resources into talking directly to voters and building the DNC’s biggest-ever grassroots field operation in Virginia.

In New Jersey, we invested six figures to flip the governor’s seat, replacing Republicans Chris Christie and Kim Guadagno with Gov. Phil Murphy and Sheila Oliver, the first African-American lieutenant governor in the state’s history.

But that’s not the only history we made in 2017. We did the unthinkable and elected Doug Jones in Alabama when everyone said it would never happen. Even before the Roy Moore news broke, we had put resources and confidence behind Jones, including investments in political, communications, digital, data, tech and research infrastructure. Over the last weeks of the election, we not only raised almost $700,000 directly for Jones' campaign account when he needed it the most, we also deployed staff and paid organizers focused on turning out Millennials, African-Americans and faith communities.

With the help of our team, we identified 241,000 voters who had not been previously identified by the campaign. And in the final days before the election, the DNC reached many of these voters to help ensure victory. But let’s be clear: Victory wouldn’t have happened without the organizing power of black women — the core of the Democratic Party. When we organize, we win. And that’s exactly what happened in Alabama.

We didn’t just focus on the sexy races at the top of the ticket. We lifted up Democrats across the board. I personally knocked on doors for a number of down-ballot candidates, including Vin Gopal in New Jersey’s 11th State Senate District. Countless people told us we would lose that race, but Democratic voters carried Vin to a 7-point upset.

We invested over $66,000 in the Washington Democratic Party to help elect Democrats like Manka Dhingra and give our party majority control of both houses.

We invested and won in deep-red districts that Trump carried in 2016. And we saw historic victories for women, LGBTQ candidates, and candidates of color — from Joyce Craig in Manchester, to Danica Roem in Virginia, to Vi Lyles in Charlotte.

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Even in races where we fell short, we saw massive swings in Democratic support and laid the groundwork for future elections by investing and organizing. In two special House elections, we sent a digital staffer to Montana and deployed dozens of staff and organizers to help Archie Parnell in South Carolina.

All of this progress was made possible by early investments, tireless organizing and our united and unyielding determination to elect Democrats up and down the ballot. In one year, we won more than 100 elections and flipped 37 state legislative seats from red to blue.

Now that we’ve demonstrated our model of success, we’re going to scale it up in 2018.

We will be announcing further investments in our state parties, registration and organizing. We want to make sure to increase turnout in 2018, because we know that when more people make their voices heard, Democrats win.

We’re modernizing with improved data and analytics to build the smartest technological and data infrastructure of any modern political party. We’ve created a Best Practices Institute — a long-term leadership center and training network for activists and organizers to learn new skills and ideas that have worked in states across the country.

And all of this has been made possible because of the incredible enthusiasm we’re seeing across the country. Two-thirds of our revenue came from grassroots donations of less than $200. We raised more money in 2017 than in any other off year since 2011. And we’re not only seeing this enthusiasm through our grassroots fundraising, but we’re seeing it at the ballot box.

One year in, I am more confident in our party than ever before. Democrats are fired up and organizing in unprecedented numbers. We’re winning elections up and down the ballot, in red states and blue states. And we’re standing up for American values every single day.

We promised that we would become Donald Trump’s worst nightmare. And unlike this president, we’re keeping our promises.

Tom Perez, a former Labor secretary, is chairman of the Democratic National Committee. Follow him on Twitter: @TomPerez