GOP Sen. Susan Collins is between a rock and a hard place on impeachment as she struggles to hold her seat

Sen. Susan Collins' fret level must be off the charts with this PPP poll of Maine voters, helpfully released under the headline "Impeachment Could End Collins' Career." The poll details how she's damned if she does support impeachment, and damned if she doesn't.

First off, she's unpopular, with just a 35% approval rating and 50% disapproval. She's losing to a generic Democrat 44-41, a cratering of support for her. A year ago, she led a generic Democrat 43-48, and "only trailed 64-21 among Clinton voters but in the wake of her vote on Brett Kavanaugh and the general hardening of partisan lines she's lost a lot of her crossover support and now trails 76-12 with Clinton voters."

But here's the juicy stuff. The PPP poll finds 53-44 support for impeachment in Maine. If Collins opposes impeachment, she earns the support of 74% of Republican voters. However, her deficit against a generic Democrat increases to 74-40, and she loses Clinton voters 83-8. If she supports impeachment, her Republican support drops down to just 36%, and she opens herself up to a primary challenger deciding to jump in. Just 14% of Republican primary voters support impeachment, with a whopping 83% opposed. Trump has 80% approval with them, Collins just 59%.

The Republican base doesn't entirely trust her, and even now, 38% of Republican primary voters say they'd rather see a different Republican in the race. PPP tested Republicans against her with Republican primary voters, who already prefer former Gov. Paul LePage over her 63-29, and Shawn Moody, who lost the governor's race last year, over her 45-36. If she goes for impeachment, the primary fight she's so far been able to avoid will likely happen.

If she doesn't oppose Trump on impeachment, she loses further with an electorate that disapproves of Trump 54-42. By the way, the impeachment numbers PPP has for Maine might be conservative.  Civiqs polling in Maine finds 59% (and so far still growing) support for impeachment.

So, yeah. Collins is walking a tightrope right now, a new experience for her in her Senate career.