Senate Republicans have blocked a bill to impose a minimum tax rate of 30 percent on American millionaires.
It's known as the Buffett Rule, named after billionaire Warren Buffett, who often points to his own low tax rate.
He has long been a supporter of higher taxes on the rich.
The Senate voted on whether to bring up the proposal for debate, but fell nine votes short.
Democrats say they won't stop fighting for the bill.
The bill would affect anyone who makes more than $1 million every year.