McCaskill told the Post-Dispatch she’d thought hard about not running this year, that she did partly out of duty, and that win or lose, she decided before announcing for re-election that this was her last campaign.

“It was not an easy decision for me to run,” said McCaskill, who was first elected to the Senate in 2006. “I had made up my mind at the end of (the 2012 election) that I wasn’t going to run again. I had never served in an office for 12 years.”

“I have a really high level of energy and a really strong work ethic, and I also get bored,” she continued. “I was worried that this was becoming a little bit of a grind. But under the circumstances — Trump did so well in Missouri (in 2016) and there wasn’t anybody else — I felt like I had an obligation to stand and fight and not just walk off the field. And so we gave it our best. But I am really at peace about being done.”