The 2018 Senate Map Puts Senator Schumer’s Filibuster Threat to the Test.

Senators Joe Manchin and Heidi Heitkamp represent states that went to Trump by margins larger than Clinton’s actual share of the vote, and will face intense pressure from their voters not to interfere dramatically in nominations. Three more Democratic Senators won in 2012 thanks in large part to big missteps by their opponents, but now face electorates that picked Trump by decisive margins. Sen. Claire McCaskill has already signaled she will fight Trump, but her state went overwhelmingly to him and she won’t have the luxury of Todd Akin as an opponent again. Sen. Joe Donnelly represents a state that clearly rejected Evan Bayh’s comeback and delivered its electoral votes to Trump by an apocalyptic margin. Jon Tester has played things smart, and represents a state that, despite giving Trump a lopsided victory, re-elected its Democratic Governor. However, his state flipped its other Senate seat from blue to red just two years ago, so he too will need to walk delicately as he faces re-election in a midterm year.

Beyond them, an additional five Democrats represent states that went narrowly for Trump: Senators Tammy Baldwin, Debbie Stabenow, Sherrod Brown, Bob Casey, and Bill Nelson. They have more wiggle room as their states went by smaller margins, and all represent states that voted for President Obama’s re-election, but they are facing midterm electorates in states that have mostly favored Republicans in off-years for the last decade. Throw in independent Angus King, who will face re-election in a state which saw its 2nd district move eighteen points rightward in four years, and Amy Klobuchar, whose state voted more Republican than the national vote for the first time in seven decades, and you can see where many in the Democratic ranks facing re-election will have to wriggle around.

Dick Durbin is gonna need a bigger whip.