A week ago, a new tax on California's billionaires looked like a near lock for the ballot.
Now traders aren't so sure, and the reason is a Democrat.
On the prediction market Kalshi, the odds of the billionaire tax reaching California's November ballot fell from 88% to 35.5%. That drop took just one week.
The trigger was reporting by Politico and Bloomberg. Both said Gov. Gavin Newsom is pushing to keep the measure off the ballot.
Prediction markets often swing hard when the news shifts.
He's racing a June 25 deadline. That's the twist here.
The person slowing a tax on billionaires is the state's own Democratic governor.
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A healthcare workers union is behind the measure. It's SEIU - United Healthcare Workers West.
The union speaks for more than 100,000 workers. It filed the plan last fall.
The idea is a one-time 5% tax on big fortunes. It would hit anyone in California worth more than $1 billion.
That's roughly 200 people. Together they hold about $2 trillion.
That's a huge pool of untaxed wealth.
The union says the money would back healthcare, food aid and schools after deep federal cuts. Backers say the state needs the cash to keep clinics open.
A one-time wealth tax like this is rare in the U.S. It would sit on top of the state's income and capital gains taxes.
Opponents argue some billionaires could just leave the state.
And the measure is not short on support. The union turned in more than 1.5 million voter signatures this spring.
Only about 875,000 valid ones are needed. State officials still have to check them before the deadline.
The politics are the real story. Newsom is widely seen as weighing a run for president.
A wealth tax fight could follow him onto the national stage. So he's reportedly leaning on the union to stand down.
A messy tax fight could weigh on a White House run.
This week he made news of his own. He said President Trump ordered the Justice Department to investigate him and his wife.
In a post on X, Newsom tied that move to his White House plans. So a measure with more than enough signatures could still die.
The rich already have legal ways to lower their tax bill. That's part of why these fights get so heated.
The date that matters is June 25. That's the deadline that decides whether the tax reaches voters in November.
The signatures got it to the door. Whether it gets through is now up to the governor.
Markets will know soon enough. The deadline is days away, and the odds are moving by the hour.
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