Sen. Mark Kirk Un-Endorses His Party’s Candidate for President

Here’s our first un-endorsement of the season:

First un-endorsement — Sen. Mark Kirk. “I cannot and will not support my party’s nominee for President.”

— Erica Werner (@ericawerner) June 7, 2016

Kirk was always likely to be one of Trump’s first defectors. He’s running a tough reelection race in a blue state. Here’s his official reason:

Given my military experience, Donald Trump does not have the temperament to command our military or our nuclear arsenal.

— Mark Kirk (@MarkKirk) June 7, 2016

At least, I guess that’s the official reason. Twitter is now the source of official political pronouncements, right?

Anyway, this might be the first time ever that a senator has un-endorsed a presidential candidate of his party. There have been plenty who never endorsed in the first place, but I’m not sure if anyone has ever endorsed and then taken it back. Historians, what say you?

Next up: Paul Ryan should become the first Speaker of the House to un-endorse a presidential candidate of his party. If enough members of Congress do this, we might even have to take the hyphen out of un-endorse and make it a real word.