Joe Biden's Route to the Democratic Nomination

A new poll finds that if Hillary Clinton doesn't run, the vice president leads the pack.

Though Hillary Clinton hasn't announced her candidacy, she's considered the clear front-runner for the 2016 Democratic nomination for president. But who will take up the mantle if she doesn't run?

According to a new CNN/ORC International poll, Joe Biden is in a solid position to fill her shoes. Without the option of supporting Clinton, the vice president garnered 41 percent support among Democrats and left-leaning independents.

Sen. Elizabeth Warren of Massachusetts, beloved among progressives, trails Biden by double digits, with just 20 percent support, while New York Gov. Andrew Cuomo and Sen. Bernie Sanders of New York took 7 percent each. Former Sen. Jim Webb of Virginia, the only politician who has made any real moves to join the race, got 3 percent support.

Although these polls are good measures of where the electorate currently stands, they aren't always indicative of the race's outcome—a test nearly two years away. In the run-up to the 2012 election, various Republican candidates had their 15 minutes at the top of the polls before eventually flaming out. A year before that race, business mogul Herman Cain led the pack, with 27 percent support. That snapshot didn't end up being quite as prescient as he would've liked.

For the past year, Biden has hedged on whether he'd make a third run for the presidency. In February, he told Politico Magazine that as far as 2016 goes, "it's either going to be me or someone else who is going to make this argument in the Democratic Party."

That argument, he said, is one on behalf of workers—fighting for income equality, a higher minimum wage. He's more of a populist than President Obama, the story quoted him as saying.

Prominent Democrats are pushing for economic populism to take center stage in the party's hurtle toward 2016. In a visit to Washington last month, New York City Mayor Bill de Blasio urged Democrats to forcefully address the economy.

"The Democrat should speak to income inequality," de Blasio said of whoever runs. "The Democrat should be willing to challenge the status quo, should be willing to challenge wealthy and powerful interests, and should marry that with the grassroots organizing strategy that epitomizes the message."

Warren and Sanders have both enjoyed grassroots support for their messages of income equality, firing up their progressive bases on an issue de Blasio says gets Democratic voters to the polls. But Biden has long promoted similar issues, too. In a September speech in Iowa, he preached the virtues of populism, disputing corporate tax inversions, and calling for reforms to aid the middle class.

Should Clinton abstain from 2016, Biden's double-digit lead over Warren and Sanders in this latest poll shows he has the most to gain. He may just be warming up.