Even senior Conservative ministers, still reeling from an announcement most did not see coming, could not spin this one: losing Justice Minister Peter MacKay leaves a big hole in their party.

"I'm sure our adversaries are rubbing their hands with glee and talking about sinking ships and deck chairs on the Titanic and whatever other allusion they can draw," Treasury Board President Tony Clement told CBC Radio's The House.

They certainly are. NDP Leader Thomas Mulcair immediately pointed to the exodus of high-profile Conservatives: ministers like John Baird and Shelley Glover, former government whip Gordon O'Connor and long time MP Diane Ablonczy.

"It seems a lot of people are abandoning Stephen Harper's ship these days," Mulcair quipped during a speech in Toronto after the news broke.

More than 30 Conservative MPs are not running in the next election — a big number, even if it is, as the government says, a natural turnover.

And the timing is certainly bad. As Clement told The House, all ministers were instructed to tell Prime Minister Stephen Harper months ago if they planned not to run in the fall election. Planning is paramount in any campaign, especially one expected to be so closely contested.

MPs Bob Dechert, Irwin Cotler, Tony Clement and Paul Dewar react to news Friday that Peter MacKay will not seek re-election this fall. 2:29

MacKay had his nomination in Central Nova and the prime minister fully expected him to run. Something changed.

MacKay has a young family and he and his wife are expecting a daughter in the fall, so his explanation that he wants to spend time with his young family is understandable. His own parents divorced when he was young, and his father Elmer, a minister in the Mulroney cabinet, was often absent as MacKay grew up. It is an experience he has publicly said he does not want to repeat for his own children.

Yes, public life is hard on families and MacKay has done it for almost two decades. Still, why he didn't tell the PM months ago remains a mystery, and senior Conservatives have admitted the timing of the departure is politically damaging.

13 Conservative seats

Harper instantly recognized this and moved swiftly to contain the damage. He was not going to let this departure happen in the disorganized way that it did with John Baird, when the PM found out about it on the nightly news.

This is all about the numbers. The Conservatives hold 13 seats in Atlantic Canada and without Peter MacKay, those seats are suddenly very vulnerable.

"Harper's approval ratings are worse in Atlantic Canada than anywhere else, including Quebec," says Éric Grenier, the poll analyst from threehundredeight.com and regular contributor to CBCnews.ca and Power & Politics. "Having a name that represents the old PC wing go away can't help."

That explains why Harper made the special trip out to the Nova Scotia Friday. He wasn't just saying goodbye to MacKay — though the affection and warmth was genuine — he was saying hello to Atlantic Canada, hoping some of the Maritime MacKay magic rubs off on him in the coming campaign.

Harper needs to convince Atlantic Canadians that the partnership he and MacKay cemented back on Oct. 16, 2003 to bring together Reformers and Progressive Conservatives, is still the core of the party. Without MacKay, that could prove a tough sell.

Keeping Red Tories in the tent

Grenier points out that when the federal Conservatives are polling nationally at around 30 per cent, as they are right now, all of the so-called "Red Tories" are parking their votes elsewhere. That doesn't bode well for Conservatives in Atlantic Canada.

Even former PC leader Jean Charest, the man who brought MacKay into federal politics, wonders what the Conservative Party will look like without the standard bearer of the PCs.

Justice minister will end his career in federal politics this fall after nearly 20 years 'for entirely personal reasons' as he focuses on family 22:26

"There is, I think, a question of whether that element of Red Tory-ism is still alive and well," Charest told The House. "We'll see where the general campaign will go and whether or not there is a place for Red Tories."

Who takes up that banner inside the party now? Charest believes progressive conservatives in the party will start to look to MPs like James Moore, Lisa Raitt, Chris Alexander and Kellie Leitch to protect that turf in the blue tent.

Grenier believes holding on to those 13 Atlantic Canada seats will not be easy for the Conservatives, even if MacKay does work the campaign, as he promised to do in his farewell press conference. And the opposition smell blood.

The Liberals say they now view MacKay's seat not just as competitive but as winnable — though their own candidate in Central Nova, David MacLeod, a military veteran, also announced he was not going to run any more for personal reasons.

Is this the end for Peter MacKay? Don't count on that.

In his press conference he said "never say never" to a return to politics, and he quoted his father's saying about never locking a door behind you.

MacKay is only 49. He will be watching the fortunes of his party closely in the next campaign. There are second acts in Canadian politics, but MacKay knows how dangerous that can be. It worked for Jean Chrétien, but then, not so much for Jim Prentice.

For now, maybe it's best to view this as a long intermission.

Evan Solomon is host of CBC News Network's Power & Politics and CBC Radio's The House. Follow him on Twitter at @evansolomonCBC.