Sen. Joe Manchin, D-W.Va., said Monday that he does not support President Biden’s proposed tax increases on corporations as part of a nearly $2.3 trillion spending proposal, potentially dealing a fatal blow to a key revenue raiser included in the infrastructure initiative. The Biden plan would raise the corporate tax rate to 28% from 21%.

The White House said the tax increases would pay for the proposed investments in the nation’s roads and bridges, transit systems, schools, and hospitals over the course of 15 years.

But Manchin — a moderate Democrat who has become one of the most powerful members of the 50-50 Senate — said that 28% is too high and could hurt American competitiveness.

“As this bill exists today, it needs to be changed,” he said during a radio interview with West Virginia MetroNews. “Bottom line is, that’s what legislation is all about. This bill will not be in the same form you’ve seen introduced or seen people talking about.”

“If I don’t vote to get on it, then it’s not going anywhere, so we’re going to have some leverage here,” Manchin said. “It’s more than just me. There are six or seven other Democrats who feel very strongly about this. We have to be competitive, and we’re not going to throw caution to the wind.”

Republicans have widely rejected the sweeping economic package, meaning that Democrats will almost certainly have to pass the measure via budget reconciliation, the obscure Senate rule the party used last month to approve Biden’s $1.9 trillion American Rescue Plan without a single GOP vote.