US Senator and Democratic Presidential Candidate Bernie Sanders speaks during a campaign event at the University of Northern Iowa | JIM WATSON/AFP/Getty US Election 2016 5 things Europe must know about Bernie Sanders He’s a socialist, but not as Europeans know it. He wants America to be more like Scandinavia. And he could be the next US president.

WASHINGTON — Just a year ago, Bernie Sanders was a curmudgeonly two-term senator from Vermont known mainly for his anti-Wall Street views and his unique brand of pseudo-socialism.

Now, with less than a week to go before the first 2016 U.S. presidential primary in Iowa, Sanders is giving the overwhelming favorite — former Secretary of State Hillary Clinton — a serious challenge.

The 74-year-old Brooklyn-born transplant to Vermont has been raking in campaign contributions, and the latest polls from Iowa and New Hampshire (which will vote soon after Iowa) show Sanders either leading or within striking distance of Clinton.

But is Sanders really a threat to Clinton? Here are five things that Europeans should know about Bernie, from his take on socialism to his view on Europe to his real chances of claiming the White House:

1. Sanders is the closest thing the U.S. has to a socialist

Referring to himself as a “democratic socialist,” Sanders has made income inequality the center of his campaign and delighted America’s far-left.

Throughout his elected life in the House and the Senate, and before that as the mayor of Vermont’s most populous city, Burlington — and well before income inequality became a top-tier issue — he focused on the growing gap between rich and poor.

Still, keenly aware that the term “socialist” carries a certain stigma in American politics, Sanders hasn’t always embraced it explicitly. “I’ve stayed away from calling myself a socialist,” he said in 1981, “because I did not want to spend half my life explaining that I did not believe in the Soviet Union or in concentration camps.”

Instead, he wraps those beliefs in a much more American framework. “For me, what democratic socialism is about is to maintain the strong entrepreneurial spirit,” Sanders told the Wall Street Journal last year.

He wants universal, single-payer health care (if you’re European, you’re probably astonished this is a debate at all in the United States) and free university for all.

But let’s be honest: an American-style socialist is a far different creature than a European one, even one whose brother, Larry, ran for parliament in the U.K. as a Green. In the European political landscape, Sanders would be a center-right or maybe center-left candidate.

2. He has pushed Hillary to the left

Alarmed by his strong showing in early voting states, the Clinton team has taken to criticizing Sanders from his right, claiming he’s a “wackadoodle” leftist with communist inclinations who went on honeymoon to the Soviet Union. (As the mayor of Burlington, he had created a sister-city program with the city of Yaroslavl, 160 miles northeast of Moscow. "Trust me, it was a very strange honeymoon," Sanders wrote in his book "Outsider in the House.")

But a better gauge of his influence is how Sanders has forced Clinton to take positions more in line with the party’s liberal activist base. Sanders has changed the substance of the Democratic contest — pushing Clinton farther to the left on issues like taxes, trade deals and the contentious proposal to build the Keystone XL oil pipeline from Canada.

On the Trans-Pacific Partnership, for example, Secretary of State Clinton supported the negotiations, but candidate Clinton came out against the deal. Clinton was closely tied to Wall Street as a New York senator, but with anger over big bank bailouts still resonating six years after the financial crisis, she has moved her tax plans steadily to the left, castigating the low tax rates and high salaries often enjoyed by financiers.

3. He fills the passion gap

Whereas Republican Donald Trump attracts voters who are furious about how the changing economy has left them behind, Sanders draws crowds of all ages — especially the young — who are furious about how the changing economy has left the top “one percent” with an enormous amount of wealth.

He also speaks to Democrats who would ultimately back Clinton in a general election, but are affected by Clinton family fatigue, her husband’s past marital indiscretions or perceptions that she doesn’t definitively stand for any particular issue.

A year ago, Clinton’s aura of inevitability stopped many from entering the race. Several governors, senators, a current secretary of state, a former vice president and the current vice president all looked at Clinton and concluded they couldn’t beat her. They saw the power of her fundraising network, her resume and her compelling narrative — the chance to break a glass ceiling and political barrier rivaled only by the election of the first African-American president in 2008.

But Sanders raised a remarkable $33 million in the last few months of 2015 — just $5 million less than Clinton, after eschewing the courtship of high-paying donors, no less. He is not backed by any fundraising Super Political Action Committee (he doesn’t even have a backpack, as Larry David famously said on “Saturday Night Live”). Clinton supporters have told POLITICO that many of them are holding out from giving until the general election.

4. Bernie on Europe

He backs Greece. He loves Scandinavian governance. He opposes NATO expansion.

Compared to the former secretary of state, Sanders lacks foreign policy heft. But when it comes to Europe, his domestic positions frame his views. He’s said that “there’s a lot to be learned from Scandinavia” where, in his view, poverty is less of a problem, health care is universal and college education is free for all.

Last summer, as debate raged over whether Greece should adopt severe cuts to come into line with the troika’s bailout terms, Sanders firmly cast his lot in with the Greek citizens.

“I applaud the people of Greece for saying ‘no' to more austerity for the poor, the children, the sick and the elderly. In a world of massive wealth and income inequality Europe must support Greece's efforts to build an economy which creates more jobs and income, not more unemployment and suffering," he said.

Clinton shied from taking a specific position on the bailout other than to say that what has happened in Greece is a “tragedy.” In a 2011 visit to Athens, she had likened Greek austerity measures to “chemotherapy” that she believed would “give Greece a very strong economy going forward.”

Generally against military action, Sanders voted against the first Gulf War, backed President George W. Bush’s post-September 11 invasion of Afghanistan and voted against the Iraq War.

On European security, Sanders’ website notes that he voted in favor of U.S. intervention in Kosovo, but doesn’t go much further on European issues. Sanders contends that he does not support NATO expansion because it inflames relations with Russia, and because of the cost; with the U.S. government facing major social spending needs at home, he says, Europeans should be footing more of the bill for the organization.

In the fall, after the Paris attacks, Sanders called for a new NATO-inspired organization that includes Russia to fight ISIL.

On Israel, “some Jewish Democrats are scratching their heads in confusion,” POLITICO’s Michael Crowley wrote. Sanders, who could be the first Jewish presidential nominee of a major political party, generally doesn’t talk about Israel on the campaign trail.

“Over his career Sanders has cast some votes and made critical statements about Israel that unnerve some in the pro-Israel community," Crowley wrote. "That's all the more puzzling, some say, given his own heritage as the son of a Jewish immigrant father from Poland whose family was wiped out by the Nazis — and someone who spent time working on an Israeli kibbutz.”

5. President Sanders?

Not so fast. Unfortunately for Republicans — who have not-so secretly been trumpeting his candidacy with a view that he would be easier to beat in the fall — Sanders faces an extremely difficult road to the Democratic nomination, much less the White House.

A long race may not be ideal for Clinton, but her deep reservoir of funds and diverse voting base mean she will probably outlast a surging Sanders. Polls show Sanders either in the lead or close behind Clinton in Iowa and New Hampshire, the pivotal early states whose voters will have their say in early February.

Still, these states, which are rural and predominately white, mirror the electoral make-up of Sanders’ Vermont; the states that follow, including South Carolina, Nevada and most of the American South, bode better for Clinton, who appears to have a much more diverse patchwork of support.

The African-American vote, so important to Obama in 2008 and 2012, comes out in force in these states, and seems likely to skew heavily in Clinton’s favor. Plus, Clinton maintains a heavy financial advantage.

The bottom line? Take those “this is 2008 all over again for Hillary” warnings with a grain of salt.

This article was corrected to clarify that Montpelier is the capital of Vermont, and Burlington is the state's most populous city.