Steven Senne/AP Photo

The 2012 general election was a great night for Democrats. Barack Obama swept to an electoral college victory, racking up 303 of those votes to Mitt Romney's 206 (although those numbers will change when the battleground state of Florida is called).

Democrats also likely picked up a net gain of two seats in the Senate. Every incumbent won re-election, and the party gained Republican-held seats in Massachusetts and Indiana, and lost one seat in Nebraska. The state of Maine is still a question mark: Independent candidate Angus King won his election to fill the seat vacated by retiring Republican Sen. Olympia Snow. King has not declared his intention to caucus with either party, but conventional wisdom is that King will be more friendly to Democrats than Republicans.

But the broader trend of Tuesday night's results was not just a victory for Democrats, it was a victory for the party's liberal base.

Incoming Democratic freshmen senators like Elizabeth Warren and Tammy Baldwin (the first openly gay senator elected) are considered to be progressive icons, rising stars with the base of their party. They defeated well-known, moderate Republican opponents- Scott Brown and former Wisconsin Gov. Tommy Thompson.

Across the country, statewide referendums yielded results not generally considered popular with conservatives.

Same-sex marriage referendums were on the ballot in Maine, Maryland, Washington and Minnesota. And the victory fell on the side of gay rights. Residents of Maine, Maryland and Washington voted to legally recognize same-sex marriage in their respective states, marking the first time gay marriage was legalized by popular vote. (In states where it's legal, it had been passed by the state legislature previously.) And in Minnesota, a measure that, if passed, would have defined marriage as between one man and one woman, was defeated.

And on the West Coast, in Washington and Colorado, another milestone: the legalization of marijuana. In Oregon, a similar measure was defeated.

Tuesday's results suggest more than just a fluke good-night for Democrats: They suggest a shift in our political and cultural zeitgeist, notes ABC's pollster Gary Langer.

"The rising influence of minority voters, the lopsided preferences of young voters, the dramatic changes we continue to see on social issues - mark more than a second term for Barack Obama. They mark, decisively, the turning of a political page," said Langer.