Instead, it was a hedge against the possibility that Ms. Snowe would retire or succumb to a primary challenge, precisely because the consequences of this would be so damaging to Republicans.
"The problem is that tactical decisions have been made into ideological decisions," says Chris Henick, a Republican strategist and former adviser to George W Bush. "Somehow a senator or congressman who otherwise has a 98% rating from interest groups suddenly might face a primary challenge just because they disagreed with the [shutdown] strategy".
"I don't think it could happen unless the media created an outcry," said Mr. Hevesi, who, because of redistricting, would face a primary challenge this year, but said he is leaving because of frustration with a "broken" system.
You write about how Arlen Specter left the Republican Party because of a primary challenge from Pat Toomey, an arch-conservative former congressman.
In the years since he ran against President Obama, Mr. McCain has moved to the right, in part because of a primary challenge in 2010.
The Senate Conservatives Fund, a PAC founded by Jim DeMint, the president of the Heritage Foundation, which has bankrolled Senator Ted Cruz, of Texas, and other highly conservative candidates, announced that it would finance a Republican primary challenge against the Minority Leader next year, because he "has a liberal record and refuses to fight for conservative principles".
I assume they picked McCain because he faces a strong primary challenge.
And, because President Trump could use a primary challenge, here are a couple of Republican women, too: 12. Susan Collins, senior senator from Maine.
It was important for her to raise money now, she told them, because she might face a Democratic primary challenge next year.
Mr. Latham is facing a strong Democratic candidate, John Norris of Ames, as well as a primary challenge, all in an area that has become far less Republican because of redistricting.
