system
Given the following post, respond as if you're commenting on Reddit:
human
Can the U.S. Vice President cast a tie-breaking vote for a 2/3 majority in the U.S. Senate?

For instance, if Puerto Rico became a state and the Senate voted 68-34 to propose a constitutional amendment, would the Vice President cast the deciding vote?
gpt
Good question.  The answer is no.  The Vice President may only cast a vote when the Senate is "evenly divided." U.S. Const., art. I, § 3.  So the VP gets no casting vote in votes requiring two-thirds (e.g., to expel a senator, trials of impeachments, treaty ratification, veto overrides, and proposals for constitutional amendments).
 
This actually came up in the otherwise excellent *John Adams* miniseries on HBO, which inaccurately depicts Adam, as President of the Senate/Vice President of the United States, casting the deciding vote to ratify the Jay Treaty.