Incumbent GOP Senator up for Re-election in 2016 will endorse Clinton over Trump

[JMT]

Lisa Murkowski.

She's in AK, a safe red state, and facing no Democratic opposition as of right now

She might be in trouble if Joe Miller mounts a third party bid and if Mark Begich gets the Democratic Senate nomination.

Miller might run again, but Begich has already said he won't run for office in 2016

[JMT]

If this report is correct, I would assume it's probably Kirk. He's running in deep blue Illinois, and is very moderate. At the same time though, he needs to actually win Republicans too, and most Democrats will support Duckworth anyways so I don't see the advantage here. I think Kirk is toast either way though, he's going to lose regardless.

I would say McCain is a possibility, but he has a tough race on his hands this year. Many conservative voters have doubts about McCain as it is, so I don't think he will want to alienate Republicans.

I know he's not up for reelection, but I would not be surprised if Lindsey Graham endorsed Clinton. He clearly hates Trump and is willing to do just about anything to stop him. Probably not likely to happen, but I wouldn't completely rule it out.