With his announcement that he’s dropping out of the Democratic primary, former New York City Mayor Mike Bloomberg becomes the latest example of a trend: self-funded billionaires running for president and getting nowhere.

When Mike Bloomberg entered the presidential race in late November, his strategy was simple: ignore the early states, where his competitors had been campaigning for months; flood the airwaves and the internet with sharp, polished campaign ads; drop an unprecedented fortune from his own pocket on the race; and convince voters that he could defeat Donald Trump when no one else could.

Perhaps the most remarkable thing about this strategy was that he wasn’t even the first person to try it this cycle. Fellow billionaire activist Tom Steyer threw his own hat into the ring, with the same plan to self-fund his way into viability (though much less money to do it with). Steyer dropped out last week.

Over the last four months, Bloomberg dropped nearly half a billion dollars on the campaign — more than his opponents combined. It bought him a surge in the polls (Steyer’s spending bought him one, too) and a brief instant of being considered a serious contender for the nomination. But it didn’t last. Bloomberg proved a bad debater, slower and clumsier on stage than his campaign-hardened peers. Questions emerged about his record. And ultimately, the American public just seems to have decided that they aren’t all that interested in selling the Democratic nomination to the highest bidder.

The tragedy here is that Bloomberg’s $500 million could have accomplished great things for the causes he cares about. Reportedly, he was opposed to a Sanders or Warren nomination — but his presence in the race may have helped Sanders by dividing a moderate wing that seems to have only lately rallied to Biden as its standard-bearer. He could have just directly supported Biden or one of his low-on-cash moderate opponents.

He could have saved his firepower for the general election (he has committed to spend, win or lose, on beating Trump). He could have directly funded — as he has throughout his life — critical activist work on the issues he cares about.

This election is showing that having billions can buy you a lot. But it won’t necessarily buy you the presidency.

Billionaires often flirt with the idea of a presidential run — and sometimes try it

What do people want when they have it all? Reasonably often, they seem to want the US presidency.

Several of America’s highest-profile billionaires have flirted with running for president, or actually run, in the past few decades. The late Ross Perot had one of the strongest showings a third-party candidate has ever had in 1992 and 1996, though he didn’t win a single electoral vote. Donald Trump, of course, won the presidency in part on the strength (at least among his supporters) of his reputation as a business leader.

Mark Zuckerberg was rumored for a while to be considering a run for president. Mark Cuban has also toyed with the idea. Starbucks CEO Howard Schultz launched a (widely derided) campaign last year but suspended it due to back problems.

It’s easy to see why the presidency is appealing to billionaires. Bloomberg, Zuckerberg, Cuban, Perot, Steyer, and Schultz all made their fortunes by steering businesses and hedge funds to enormous commercial success, and it’s easy for them to conclude that they could do the same for the country. When you’ve earned billions of dollars and have a world of opportunities open to you, of course you’d want to have the chance to make a difference in the world and push for your ideals.

But hey, billionaires: Running for president is actually a bad idea. You’re very unlikely to win, it’s not clear that you have the skills to do the job well, and there are much, much better ways to make a difference in the world with your billions.

The skills that make you rich don’t necessarily make you good at politics

Here’s an argument for billionaires in politics, at least as long as they made their fortunes themselves: It takes an incredible work ethic, good management skills, dedication, and a gift for setting priorities to turn a small company into a prosperous multinational one. Those all seem like skills that’d be useful in politics too, right?

This is the case Perot made for himself. “See, there’s a lot I don’t understand,” he said in a debate with George H.W. Bush and Bill Clinton. “I do understand business. I do understand creating jobs. I do understand how to make things work. And I got a long history of doing that.”

Billionaires since have echoed him. Bloomberg cited the “pragmatic approach” of business leaders. Schultz’s website prominently featured his successes at Starbucks. Trump leaned on his business background, telling voters in early campaign ads, “My opponents have no experience in creating jobs or making deals.”

The problem is that it’s not really clear the skills transfer. In the course of their meteoric professional careers, billionaires mostly interact with people who work for or with them, and lots of political concerns that rank highly for everyday Americans aren’t areas they know anything about.

This election season, one of the most notable things about Bloomberg and Steyer was that they were both bad debaters. While nearly all of the leading candidates had some sharp moments during the debates, Steyer was frequently mocked for looking unnatural, and Bloomberg’s polls took a sharp dive after his first debate, where he was constantly off balance.

Politics is actually a skillset. It’s quite different than running a company — it requires a lot more debating skill, poise, and audience engagement.

Billionaires often have high approval ratings, but their image tends to take a battering when they enter the public arena. In part, that’s because people were evaluating them as (hugely successful) people, not as politicians, and they’ll inevitably turn off many voters as they start to take stances on the issues. In part, it’s because negative stories that probably wouldn’t have come out had they stayed off the political radar are now more likely to emerge.

And in part, it’s because they typically don’t seem to be good at campaigning. Certainly, not all politicians are charismatic. But especially in a bid for the presidency, charisma makes a big difference, and most of the CEOs in the public consciousness do not possess it — at least not the kind that gets millions of voters fired up.

Money doesn’t necessarily seem to make up for this deficit. Some political science research actually suggests that past a certain point, money does a candidate no good at all. In an environment where both candidates are spending lots of money on ads, they may not change any minds. The most exhaustive research on this study is a meta-analysis of more than 40 studies of persuasion campaigns in elections, which the authors bolstered by conducting extensive studies of their own. The results? Contacting voters in a general election — whether by ads or door-to-door canvassing — just doesn’t seem to change any minds.

One billionaire, Meg Whitman of California, found this out the hard way. In 2008, the New York Times named her among women who might become president of the United States someday. In 2010, she ran for California governor, spending $144 million of her fortune (then valued at $1.3 billion). She lost badly to Jerry Brown, who spent $36 million.

Not all billionaire runs for office have ended in failure — Bloomberg won two mayoral terms in New York, and of course Trump won the presidency (though he arguably got more of a boost from being a TV star than from being wealthy). And Bloomberg had some reason to believe he was different — he is, in fact, way richer than Trump or Whitman, and spent far more money on his campaign than either of them ever did. Add to that an actual record of electoral success in New York, and it’s hard not to blame him for thinking this time might be different for this billionaire.

But that’s not how things turned out. The takeaway for the ultra-rich? If the point is to advance your vision, there are wiser ways to spend your money than running for public office.

Billionaires have great options for pursuing their vision and ideals

So what are you supposed to do if you’re a billionaire who wants to fix America?

If you really have the itch for politics, you can support recruitment efforts and primary campaigns to get promising candidates into local and state offices, where they’ll build the experience and contacts they need to run for president.

Steyer has done this, and seen some considerable successes. He gave $33 million to voter mobilization effort NextGen Rising, which registered more than 250,000 young voters in 11 states with congressional swing districts. That was part of $123 million in giving for the midterms, and Forbes estimates that his contributions swung some key House races. He could redouble these efforts for 2020, getting more voters registered and mobilized for whichever candidate does emerge from the Democratic primaries.

That’s just one idea. He could pour more money into other causes as well, with dozens of options that are likely to get him better results for the money than a quixotic campaign for president. Bloomberg has been a big funder of efforts to combat gun violence and increase voter turnout. He can do genuine good there.

In other words, part of why billionaires shouldn’t run for president is that there are much higher-leverage options for their time, energy, and money — options that will advance their goals a lot more effectively.

But is that good for the rest of us? A lot of people have mixed feelings about billionaire philanthropy, at least once billionaires step away from uncontroversially great projects like vaccinating children and combating malaria, areas where individual billionaire philanthropists have saved millions of lives. Rob Reich, a philosopher at Stanford University, has argued that we should be more skeptical of how much leverage billionaires have to advance their civic ideals with their fortunes. There are some signs that the American public felt similarly uncomfortable — and that it damaged the prospects of the self-funded candidates.

Those are legitimate concerns. My view is that we should judge billionaire philanthropy on the merits — laud them when they do good, encourage better when they waste their money, and criticize those projects that advance goals we don’t share. If Steyer and Bloomberg put their money behind projects that are cost-effective and serve a broader public purpose, I’ll be thrilled for them — and for us.

Going that route may be a little less dramatic than running for president. But CEOs and hedge fund managers should care about results, right? The $768 million the Clinton campaign spent is more than we’ve spent on efforts to eradicate malaria with gene drives, hundreds of times more than we’ve spent on improving our electoral system with new voting systems, and significantly more than we have invested in managing emerging technologies.

Anyone running on their “business sense” should ask themselves the most cost-effective way to achieve the results they dream of — and typically, the answer won’t be with a campaign for president.

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