How might only one senator slow down or stop consideration of a bill? (bill, calendar, hold, unanimous consent)

A senator can slow down or stop consideration of a bill through a process known as a "hold." Here are the steps:

1. Hold: A senator may place a hold on a bill to express his or her objection. This is a formal notification to the party's leadership. The senator doesn't need to give a reason for the hold, and it can be done in secret.

2. Effect on the Calendar: Once a hold is placed, the bill is effectively removed from the Senate's calendar. This means it won't be scheduled for floor debate until the hold is lifted. This can significantly slow down the legislative process.

3. Unanimous Consent: The Senate often operates under "unanimous consent" agreements, which means that any senator can object to a bill and effectively stop its progress. If a senator has placed a hold on a bill, they can refuse to give their consent, preventing the bill from moving forward.

4. Lifting the Hold: The hold can be lifted if the senator who placed it decides to do so, or if a supermajority of 60 senators vote to invoke cloture, which ends the hold and allows the bill to proceed to a vote.

In this way, even a single senator has a significant amount of power to slow down or stop consideration of a bill.