Senate Republicans have spent most of the year justifying their blockade of Supreme Court nominee Merrick Garland by saying the next president should fill Antonin Scalia's empty seat, but their obstruction probably won't end there.
Senator John McCain, who is facing his own challenge in Arizona, spoke to a Philadelphia radio station and said Senate Republicans will unite to block President Hillary Clinton's nominees.
"I promise you that we will be united against any Supreme Court nominee that Hillary Clinton, if she were president, would put up," McCain said. "I promise you. This is where we need the majority and Pat Toomey is probably as articulate and effective on the floor of the Senate as anyone I have encountered."
Even if Democrats gain control of the Senate, it's highly likely that Republicans will filibuster President Clinton's Supreme Court nominees.
In that event, Senate Democrats will have all the justification they need to end the filibuster once and for all and move forward with simple majorities. There will be no other choice.
If Democrats do not gain control of the Senate, we're looking at the possibility of a permanent vacancy on the Supreme Court and possibly even dozens of other federal jurisdictions where Republicans have already committed themselves to blocking lower court nominees.
I probably don't need to spell out what that could mean, but suffice to say a permanent vacancy would be a legal quagmire that could leave very big questions without a clear answer if a deadlocked court cannot rule for or against any particular issue.
Ian Millhiser at ThinkProgress has more analysis on what this could mean and it truly is nightmare fuel.
If you live in Arizona, get out and vote for Ann Kirkpatrick.