Tech billionaire Elon Musk is already flexing his newfound political muscles even before his ally, President-elect Donald Trump, has taken the oath of office.

Musk helped lead a revolt on Wednesday to try to stop a bipartisan funding bill, a direct challenge to the authority of House Speaker Mike Johnson and other Republican leaders who helped craft the measure. And in a remarkable twist, the revolt appeared to succeed, at least for a day, throwing budget negotiations into chaos and increasing the likelihood of a government shutdown this weekend.

“Yes,” House Majority Leader Steve Scalise, R-La., confirmed to reporters Wednesday evening when asked if the current bill is now dead.

Musk posted about the funding bill more than 100 times on X throughout the day. He repeatedly called the bill “criminal” and urged his supporters to call their representatives, but also posted memes, including one in which he took a sword to the bill and another in which he referred to the “Kill Bill.” “films by director Quentin Tarantino. Later that day, the phrase “Kill Bill” was on X’s list of trending topics in the US

Musk also issued a midday warning: “Any member of the House or Senate who votes for this outrageous spending bill deserves to be voted out in two years!” And when The Hill newspaper published an article about the warning on its website, Musk underscored his point by approvingly posting a screenshot of the headline.

Some of Musk’s posts were inaccurate. He said a salary increase proposed by Congress would be 40%, while the maximum possible salary increase in 2025 has already been set at 3.8%, according to the Congressional Research Service. He also said the bill provides for “funding of bioweapons laboratories,” citing a screenshot from the bill’s text that refers to “biocontainment laboratories” to better prepare the U.S. to combat infectious diseases.

And he retweeted a false post claiming the bill included $3 billion for a new NFL stadium in Washington, D.C., and said it “should not be funded by taxpayer dollars.” That’s not it. The bill transfers responsibility for RFK Stadium from the federal government to the capital, the redevelopment of which local officials have pushed for the Washington Commanders, who currently play in Maryland. The bill does not appropriate funds related to the site, expressly prohibits the use of federal funds for a stadium there, and requires the district to pay all costs associated with the transfer.

His successful lobbying led Democrats to offer new nicknames for Musk, including “shadow president” and “co-president.”

Musk announced his opposition to the bill at 4:15 a.m. ET on Wednesday.

“This bill should not be passed,” he posted on his social media app X.

The statement exposed Musk as one of the first politicians to speak out against the bill, but 13 hours later Trump himself expressed his approval. What happened in between was an angry online campaign led by Musk to try to defeat the bill, which he said was “criminal” because of its 1,547-page length and the costs involved.

The measure would have maintained funding for the government until mid-March. The shutdown is expected to begin at 12:01 a.m. Saturday without action from Congress.

Musk has never held political office and until recently had rarely voted, but his influence is growing due to the combination of his enormous wealth, online fame, ownership of X, and his financial and personal support for Trump’s political comeback this fall.

Sen. Jeanne Shaheen, D-N.H., was one of several Democrats who questioned whether Trump would be overwhelmed by Musk.

“You have to ask Donald Trump – whether Elon Musk makes the decisions,” Shaheen said on Wednesday.

A Trump transition team official questioned why Trump waited to announce his opposition until hours after Musk and others criticized the bill: “He left everyone wondering what he wanted to do. All eyes were on him. When he moved, it was over. He’s president before he’s president.”

President Joe Biden’s term ends on January 20th.

Musk’s position in the Trump administration will be that of a non-governmental adviser, as he co-heads a government efficiency commission. Therefore, his actual authority is more difficult to measure than that of a Cabinet secretary or a full-time White House staffer.

Musk did not immediately respond to a request for comment, including whether he plans to play a similar role in other legislative debates next year.

Sen. Bernie Sanders, I-Vt., said on X: “Democrats and Republicans have spent months negotiating a bipartisan deal to fund our government. The richest man in the world, President Elon Musk, doesn’t like it. Will the Republicans kiss the ring? Billionaires cannot be allowed to run our government.”

Musk, the CEO of Tesla and SpaceX, spent more than $250 million this year to support Trump and other Republicans in the Nov. 5 election. Since then, his own wealth has risen to over $450 billion, making him the richest person in the world, according to the Bloomberg Billionaires Index. SpaceX is a large government contractor.

On the social media app Bluesky, Rep. Maxwell Frost, D-Florida, said: “Unelected Republican co-President Elon Musk rejected the bill to prevent the government shutdown on Friday.” All he had to do was post a few social -Write media articles.”

Musk seemed to acknowledge his influence, responding to a compliment on X that touted Musk’s power with a “greeting face” emoji.

Several Republican lawmakers said they were glad Musk intervened, but they stopped short of giving him all the credit or blame for the breakdown in budget negotiations.

Rep. Marjorie Taylor Greene, R-Ga., said: “Elon made a pretty serious post there. But you know, that’s the mood of the American people. That’s why we won on November 5th. Everyone is tired of overspending.”

When Sen. Ted Budd, R-N.C., was asked about Musk’s comments on the bill, he said, “He’s very influential.”

At least one conservative lawmaker, Rep. Tim Burchett, R-Tenn., declined to give Musk credit. He said he was against the funding bill before the billionaire.

“I appreciate Elon Musk following my lead,” Burchett said on CNN.

Sen. Josh Hawley, R-Mo., said Musk tapped into or reflected “a lot of anger out there.”

A Senate Republican aide who was granted anonymity to speak candidly said Musk’s role was not critical and he risked a backlash. “I think the CR was already screwed without Elon, but I wouldn’t be thrilled with him playing that role if I were Trump,” the adviser said, using the acronym for “ongoing resolution.”

There was no guarantee that Musk’s opposition to the bipartisan bill would succeed. When he announced his opposition, betting site Polymarket gave a 12 percent chance of a government shutdown this weekend. As the day progressed, the probability increased to 40% given the flood of tweets from Musk.

According to the app’s publicly viewable data, many of his posts on X have been viewed tens of millions of times. His first announcement opposing the bill was seen 32 million times, and a post with a photo of the bill and the question, “Have you ever seen a larger piece of pork?” was seen 27 million times.