[MNlurker]

My guess?

They (I'm focusing solely on R's) don't like the idea of being held accountable for votes and actions. They liked being able to raise "PAC" money for themselves to take with them to when they finally decided to retire.

Instead they are being threatened with primaries when they don't stand for the ideals they promised to uphold when they ran. It would drain their retirement funds to have to primary and then run a general campaign they would not be assured of conservative support in.

Have I really become this much of a cynic...?

[Reagan69]

He probably wants to spend more quality time with family/s

[kalee]

Sadly I think you may be correct.

[iceskater]

You aren’t alone in your cynicism.

[TomGuy]

They liked being able to raise "PAC" money for themselves to take with them to when they finally decided to retire.

McCain used some $20 million 'left over' from his presidential campaign to help his senate reelection run.

That seems like it should be investigated for ethics violations or outright campaign finance fraud. People gave that money for his president run. Why did he bank it? He was, after all, using the FEC Presidential fund to campaign, because he ran out of donated funds mid-stream during the primaries.