Tuesday’s Blue Wave was powered by voters of color. That’s a key takeaway strategists in both parties are clocking as they pore through the results. In a memo obtained exclusively by TIME on Wednesday and soon to circulate among the Democratic National Committee’s bigwigs, two of the Democratic Party’s veteran strategists argue that the blowout would not have been possible without that crucial realignment, one that has enormous consequences for 2028’s presidential field.

“Hispanic and Black voters not only turned out at a massive rate, but also swung back towards Democrats in terms of support levels, relative to the 2024 presidential election,” Tom Bonier and Simon Rosenberg wrote in Wednesday’s memo.

To be clear, every major demographic group shifted left in these midterms, offering a stunning rebuke of President Donald Trump and his brand of the Republican Party. “The final popular vote margin for the House will take weeks to determine, but at this point Democrats are on track to have the largest popular vote margin in a midterm election since 1974,” Bonier and Rosenberg write. “Voters of color were the driving force behind the blue tsunami.”

But the shift in voters of color proved pivotal in many cases. Hispanic voters had a 28-point move leftward from 2024’s presidential levels, according to a New York Times analysis. Black voters moved nine points. Asian American voters? They moved 17 points.

The party’s base “came home,” in the words of one Democratic strategist on Wednesday. “Back to normal” was the verdict of another.

Hispanic voters proved particularly enthusiastic to cast their ballots. A Bonier-Rosenberg analysis of early-vote data showed Hispanic turnout easily surpassing 2022’s midterms, and potentially topping even the 2024 presidential numbers, before Election Day.

This shift will have big implications for the candidates mulling presidential runs, but also for the party’s decision last year to rearrange its primary calendar. The DNC’s choice to elevate South Carolina’s presidential primary to lead-off position for 2028 drew some second-guessing from within the party. That decision now looks even more prescient, as it further empowers the true spine of the Democratic Party. A full 26% of South Carolina voters on Tuesday were voters of color, according to exit polls. That’s a far cry from Iowa and New Hampshire—the traditional starting pistols in the presidential race, where less than 10% were voters of color, per exit polls.

Democrats spent much of this cycle courting voters of color they had lost in 2024 by arguing that Trump’s economy had left them behind. Tuesday’s results appeared to prove the wisdom of that effort, Bonier and Rosenberg argue in their memo, pointing to Texas’ Webb County as a prime example. Comparing Trump’s 2024 tally with Sen.-elect James Talarico’s win, the Hispanic vote there swung a full 50 points away from Republicans.

“To be clear, 50-point swings don’t happen on turnout alone. In fact, a huge component of this result was clearly due to Trump voters crossing over to support Democrats in this election,” the Democratic strategists wrote to other insiders.

“Voters of color took a stand in this election, a stand to protect their future,” the memo reads. “Democrats now have the opportunity to deliver where Republicans have failed.”