Sen. Ted Cruz (R-TX) will push a 60-vote threshold, meaning he's threatening to filibuster, on a clean debt ceiling increase extension.
Cruz's office confirmed the Texas senator's plans to TPM on Tuesday afternoon.
Cruz's move means lawmakers will need to rally 60 votes in the chamber to pass the bill, and Democrats only control 55 votes.
The announcement came the same day that House Republicans dropped a previous debt ceiling increase proposal and embraced a clean hike instead.
That decision sparked outrage from tea party groups with Tea Party Patriots co-founder Jenny Beth Martin calling it a "complete capitulation."
The Senate vote on the clean debt ceiling bill is likely to come shortly after the House vote planned for Tuesday evening.