Here's the race Democrats should be watching for a preview of 2020.
It's early, but a key battle in the 2020 presidential race has already begun in Illinois. Billionaire Hyatt Hotel heir and Democrat J.B. Pritzker has just announced he'll be running for governor against fellow almost-billionaire and incumbent Republican Governor Bruce Rauner in 2018.
As spicy as the political atmosphere in Illinois is, the reason this election is nationally important is because it should serve as a key test case in a fierce debate among Democrats about how to defeat President Donald Trump.
SPOLIER ALERT! If the Democrats pay close attention, they're about to see that candidates like Pritzker should be avoided like the plague.
First a little background. Pritzker was born into one of the wealthiest families in America, but he's also a private investor who was a relatively early player in launching venture capital tech investing in Chicago. He's been one of the Democratic Party's most generous and important donors for two decades.
Now, he's challenging Rauner, who overcame tough odds by winning the governor's mansion in 2014 in a blue state, but has presided over a bitterly divided legislature and an ongoing budget stalemate. That stalemate has made Rauner vulnerable in the polls, and the Democrats smell blood.
For those Democrats who say putting another billionaire with private sector business experience on the ballot is the best way to oust Republicans like Rauner, Pritzker's candidacy could make or break that argument.
Rauner's "run Illinois more like a business" policy still has its fans, but his approval rating is stuck in the 30-35 percent range and the lack of a working budget in Illinois is a national embarrassment. Those backing Pritzker feel like they can steal the popularity of Rauner's businessman independence, but with a candidate who is more liberal.
Simlarly, many national Democrats believe President Trump has been allowed to skate on his patchy business record. A confirmed multi-billionaire like Pritzker, (net worth $3.4 billion), could provide a strong contrast, and attract white middle and lower middle class voters in areas outside of Chicago.
Further, liberals understand that candidate Trump benefited enormously from his powerful name recognition. In Illinois, especially in vote-rich Chicago, Pritzker enjoys almost Trump-like name recognition.
Finally, the case for Pritzker is about the race for cash. Rauner has expressed his willingness to spend millions of his own dollars in his re-election efforts and the Chicago Tribune reports that some key state Democrats believe they need Pritzker and his cash to counter that.
So why is Pritzker still a bad bet, both for governor of Illinois and as a relative prototype for a Democratic presidential candidate? Because he's going to lose. And he's probably going to lose very badly.
A recent straw poll of Illinois Democrats put Pritzker in fifth place among a list of 9 possible candidates. Depending on how much he spends in the coming months could change that, but he has a big hill to climb. And to make matters worse, he won't be the only Democrat trying to use his money and name-recognition to garner more Democratic support. One of Pritzker's opponents is none other than millionaire Kennedy family scion Chris Kennedy.
Meanwhile, the guy leading the pack is State Senator Daniel Biss, whose campaign literature begins and ends with reminders that he is not a millionaire. Biss is way ahead in the early Democratic Party polls.
That seems to support the argument that backing billionaires undermines the Democratic Party's traditional appeal to lower middle class and poorer voters. Clintons' enormous wealth accumulation while operating in and out of public service, for example, hurt Hillary Clinton's presidential chances both in the Democratic primaries and the general election. Progressive candidates like the non-millionaire Senator Bernie Sanders did well precisely because he was able to "walk the walk" so effectively.
Beyond money and class issues, Pritzker is also a weaker candidate because he's truly a product and member of the political class. Pritzker and his family have been major Democratic Party donors for decades. His sister Penny rode her financial support for then-candidate Barack Obama to the Commerce Secretary spot in his cabinet. At some point, big donors like to get off the sidelines and get on the political stage themselves. And when they do, it can be hard to stop them.
President Trump's unique appeal was predicated on the fact that despite his wealth, he was seen as the consummate political outsider. Pritzker is far from that with his years of political fundraising and schmoozing with elected officials.
He even once ran for office, unsuccessfully, in a 1998 election for the U.S. House of Representatives. If the Democrats ever want to bring back the white middle class and lower middle class to the fold, he's just about the polar opposite of the kind of candidate they'll need.
But as they say in sports, "that's why they play the game." Those Democrats who think a well-connected billionaire type can be a model for their more important future battles will get their chance to prove their case with the Pritzker campaign.
If he does manage to succeed, other more nationally viable billionaire liberals like Bloomberg or former Starbucks CEO Howard Schultz will then become more likely to challenge Trump on the national stage. If he loses, the progressive wing of the party gains a significant victory.
Commentary by Jake Novak, CNBC.com senior columnist. Follow him on Twitter @jakejakeny.
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