Sen. Bernie Sanders, I-Vt., is seen in this 2014 file photo as he speaks on Capitol Hill in Washington. (AP Photo/Cliff Owen)

Bernie Sanders, the independent senator from Vermont, will seek the Democratic nomination for president next year. Most pundits agree he can't defeat the presumptive nominee, former Secretary of State Hillary Rodham Clinton. Nate Cohn explains why in The New York Times:

The left wing of the Democratic Party just isn’t big enough to support a challenge to the left of a mainstream liberal Democrat like Mrs. Clinton. ...

The party includes a large number of less educated, more religious — often older, Southern or nonwhite — voters who are far from uniformly liberal.

The majority of Democrats and Democratic primary voters are self-described moderates or even conservatives, according to an Upshot analysis of Pew survey data from 2014 and exit polls from the 2008 Democratic primary.

Sanders's strategy, however, won't be to run to the left of Clinton, as many commentators have assumed. His campaign won't be about mobilizing the party's left flank or its base, its highly educated members living in coastal cities. Instead, as he explained to Simon van Zuylen-Wood for a profile in National Journal last year, his goal will be to appeal to working-class white voters, many of whom might describe themselves as moderate or even socially conservative in surveys.

If that seems insane, well, maybe it is. Sanders, though, likes to talk about how he consistently wins by large margins in his home state, which shows that he has in fact won the allegiance of many otherwise conservative voters. His supporters, possibly, feel alienated from the political and financial elite that makes up the establishment in both parties. No Democrat represents that elite better than Clinton.

Sanders's policies will be to her left, but in his view, his constituency will be to her right. The real question for him is not about the strength of his support among committed liberals, but whether he can persuade moderate Democrats outside of Vermont to vote for him and his radical agenda.

To see how this paradoxical strategy might have a chance of succeeding, read Timothy P. Carney's column in The Washington Examiner. He notes that it's often the radicals in both parties who are able to find common ground and hash out compromises, and work toward shared goals such as reforming the National Security Agency and closing the Export-Import Bank.

"Plenty of moderates in both parties are principled, too. But as a rule, the center is populated by opportunists, corporatists and political windsocks, unwilling to stand on principle lest they end up on the losing side," Carney writes. "K Street runs through the political center of American politics, and doesn't have much intersection with the Left or Right edges."

If other conservatives feel similarly, Sanders might just make the Democratic primary competitive.

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What's in Wonkbook: 1) Sanders 2016 2) Opinions, including Roberts and Mooney on Pope Francis and global warming 3) The most expensive Medicare drugs, and more

Chart of the day:  "For decades, labor’s share of American national income has shrunk while the share that goes to profits has expanded. There are now tantalizing signs that labor may finally be gaining ground on capital. Workers in the first quarter of the year recorded their biggest annual gain in pay since 2008, evidence that a steady decline in unemployment is finally having an effect on paychecks." Greg Ip in The Wall Street Journal.

1. Top story: Sanders meets the press

Sanders lays down his challenge to Hillary Rodham Clinton. "He seems an unlikely presidential candidate — an ex-hippie, septuagenarian socialist from the liberal reaches of Vermont who rails, in his thick Brooklyn accent, rumpled suit and frizzy pile of white hair, against the 'billionaire class' taking over the country. ... The contrast between the two candidates is stark: his authenticity and unvarnished rhetoric to her careful script; his unabashedly liberal agenda to her years of triangulation; his grass-roots campaign to her paid army of staffers and super PAC allies. Another danger for Clinton: Because of her dominance at the outset, any surge by Sanders or another challenger could be interpreted as a sign of her weakness and erase her aura of inevitability." Paul Kane and Philip Rucker in The Washington Post.

His speech got right down to brass tacks. "In a speech that lasted only five minutes just outside the Capitol building, the 73-year-old senator from Vermont declined to invoke lofty imagery of a Sanders White House. Instead, he laid out his agenda of economic populism and how his brand of Democratic socialism can best tackle the 'enormous issues facing this country.' ... The senator didn't waste any time before diving into policy, distilling into the short speech what he sees as the great menaces of America's middle class: the Koch brothers, Citizens United, the country's 'crumbling infrastructure,' the billionaire 'top one percent' who own 'almost as much wealth as the bottom 90 percent.' And he urged the media, including the scrum of reporters gathered for the event, to focus on the "serious debate over serious issues" in lieu of 'gossip' and 'making campaigns into soap operas.' " Rebecca Nelson in National Journal.

With a series of interviews, he's already taken more questions from the press than Clinton. "Earlier this week, National Journal's Zach Cohen counted all of the times Clinton has answered press questions since she announced her presidential campaign on April 12. Cohen counted just seven 'answers'—about half of which ignored the actual question. ... Sanders, who needs all the press attention he can get, kicked off his presidential campaign by fielding a barrage of questions from TV news reporters in interviews Wednesday. Over the course of one five-minute exchange with MSNBC's Andrea Mitchell on Wednesday, Sanders answered seven separate questions." Patrick Caldwell in Mother Jones.

Her rhetoric has shifted to the left, which limits Sanders's chances. "The issues Sanders identified as his causes in this campaign — economic justice, climate change, and reining in the influence of big spenders in politics and government — are all now standard fare for the much better funded, much better known, and much more big-D 'Democratic' Clinton. ... Like Sanders, Clinton has mocked climate-science deniers and has made campaign finance reform a pillar of her agenda in this campaign — even as she solicits money from megadonors." Jonathan Allen at Vox.

JONATHAN BERNSTEIN: Sanders will force Clinton to be specific. "Even if Sanders runs a strong campaign, he isn’t going to win the nomination. ... But Sanders (and former Governor Martin O’Malley of Maryland) will make it harder for Clinton to avoid making any commitments on what her policies will be if she is elected. She will still have an incentive to duck as many issues as possible to increase her flexibility in the general election and if she becomes president. But she’ll have to take part in at least a couple of debates. The more the next 10 months or so resemble a real nomination battle, the more she’ll be pushed to endorse specific parts of the Democratic agenda." Bloomberg View.

2. Top opinions

ROBERTS: Pope Francis could achieve a breakthrough by defining climate change as a moral issue. "The Pope's statement carries unique significance for the simple reason that he has unquestioned moral authority for millions of people. He threatens to situate the fight against climate change as a deeply moral issue, a matter of God's work on earth. Once it is so situated, it will slowly and inexorably drag culture and politics along in its wake. The right, which is entirely comfortable deploying moral arguments, understands this better than the mainstream, center-left environmental establishment. Large swaths of the center-left establishment (especially among the foundations that fund things) are besotted with dreams of technocracy and bipartisan civility." Vox.

MOONEY: Obama made the mistake of talking about the issue in economic terms from 2008 to 2010. "Those were the days, during the Great Recession, when the White House tried to persuade the world to act on climate change through a message about “green jobs.” This was about the economy, the White House told us. And, it was about advancing new technologies — smart meters and wind farms and solar panels. ... Many would say it was politically impossible no matter the argument, but the fact was that climate solutions couldn’t make it through Congress. Obama II on climate change, though, has often adopted a moral framing, making sure to talk about 'our children,' our 'grandchildren' and 'future generations.' It still may not be enough to get any legislation through this Congress — and in his second term, the president may be less guarded and more frank in his approach — but it also reflects a broadly shifting message." The Washington Post.

BOUIE: Clinton gave an impressive speech about criminal justice. "There’s plenty to quibble with in Hillary Clinton’s speech on mass incarceration and criminal justice reform, which she gave on Wednesday at Columbia University. ... But the problems and omissions in Clinton’s speech shouldn’t blind us to the fact that it’s a remarkable piece of political rhetoric, both in its own right and for what it says about American politics in 2015. Two days after riots in Baltimore—at a time when most of the presidential field is either silent or contemptuous—Clinton has stepped out front with a forward-looking agenda on bringing people out of prison, a definitive rebuke to the 'law and order' politics used by her husband throughout his career. Not only did Clinton call for an end to 'the era of mass incarceration,' but she also connected our prison population to broader patterns of inequality." Slate.

BROOKS: What Baltimore needs is stronger social bonds, not more government programs. "In 2013 the federal government spent nearly $14,000 per poor person. If you simply took that money and handed it to the poor, a family of four would have a household income roughly twice the poverty rate. ... Saying we should just spend more doesn’t really cut it. What’s needed is a phase shift in how we think about poverty. Renewal efforts in Sandtown-Winchester prioritized bricks and mortar. But the real barriers to mobility are matters of social psychology, the quality of relationships in a home and a neighborhood that either encourage or discourage responsibility, future-oriented thinking, and practical ambition." The New York Times.

KRUGMAN: There's one question of character the press should ask of candidates. "You shouldn’t care whether a candidate is someone you’d like to have a beer with. Nor should you care about politicians’ sex lives, or even their spending habits unless they involve clear corruption. No, what you should really look for, in a world that keeps throwing nasty surprises at us, is intellectual integrity: the willingness to face facts even if they’re at odds with one’s preconceptions, the willingness to admit mistakes and change course. And that’s a virtue in very short supply." The New York Times.

3. In case you missed it

As many as one in six species confronts extinction as the earth warms, according to a new analysis. "In a study published Thursday in the journal Science, Mark Urban, an ecologist at the University of Connecticut, also found that as the planet warms in the future, species will disappear at an accelerating rate. 'We have the choice,' he said in an interview. 'The world can decide where on that curve they want the future Earth to be.' " Carl Zimmer in The New York Times.

Neither party supports Obama's proposal for a new authorization of war. "It has been nearly three months since Obama, responding to congressional demands and his own pledge to seek legislative blessing, sent proposed war authorization language to Capitol Hill. Now, the subject appears to be dying a quiet death. ... It is the Democrats who have argued for narrowing Obama’s latitude. They worry that vague language in his proposal, including about the possibility of ground troops, would deprive Congress of its ability to check executive action and allow Obama or his successor unlimited expansion of global military actions. Republicans have said the language is too restrictive and would limit U.S. ability to respond effectively to a global threat." Karen DeYoung in The Washington Post.

A few pricey medications account for a large fraction of Medicare Part D spending. "Costly drugs for diseases, such as cancer and multiple sclerosis, account for more than a quarter of spending on prescriptions for America’s elderly and disabled, despite being used by relatively few patients, according to newly released data from Medicare’s prescription-drug program. The data, which cover prescription-drug claims paid in 2013, show that out of nearly 3,500 drugs prescribed that year, roughly 400 with a cost of $3,000 or more per beneficiary added up to $26.5 billion." Joseph Walker and Anna Wilde Mathews in The Wall Street Journal.