Confirmation requires a majority, or 50 Senate votes with Vice President Mike Pence acting as tie-breaker. Currently, Republicans hold 53 Senate seats. Thus, if four or more Republicans oppose a vote, and all Democrats also are opposed, a nominee will be blocked.
Here’s how Senate Republicans felt in 2016, and what they’ve said publicly now. Click here for a Google doc with links to the original source for all statements and quotes we found… More here.