Washington (CNN) Early voting continues to be explosive, as an energized American electorate weighs in on its government.

As of early Tuesday morning, at least 33 million people have voted early nationwide, according to data collected by Catalist, a data company that works with Democrats and others, to compile counts of ballots cast before Election Day, either early in-person or by mail.

That's far more than the 22 million early votes cast in the entire 2014 election.

The data suggests an electorate deeply engaged in voters' first real opportunity to offer a verdict on the presidency of Donald Trump, who has actively tried to turn the election into a referendum on himself.

Encouraging signs for Democrats include a clear surge in young and first-time voters in the early voting data and a larger percentage of women voters, who have appeared supportive of Democrats in recent national polls.

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