HALIFAX - Stephen Harper's steadfast refusal to allow maverick Nova Scotia MP Bill Casey to return to the Conservative party has ignited an internal backlash at a time when each seat is critical to building a majority government, say party stalwarts.

In Amherst, N.S., Ron Elliott, 79, has prided himself on being the first to plant a Tory lawn sign during the past 20 provincial and federal elections. But in an interview Monday, he said Harper's decision will prompt him to end his long history of supporting the federal party in the next election.

"He (the prime minister) doesn't take anybody else into consideration," Elliott said of Harper. "It's his way or the highway."

Casey, the MP for Cumberland-Colchester-Musquodoboit Valley for much of the last two decades, was booted out of the party by the prime minister for voting against the federal budget in March.

The MP defied his boss because the budget changed the federal equalization formula, a move Casey says gutted the 2005 Atlantic Accord -- a federal-provincial deal that was supposed to protect the province's natural resource revenues from federal clawbacks.

Last week, after Harper and Nova Scotia Premier Rodney MacDonald reached a deal they claim will restore the financial benefits of the accord, party members like Beth Stanfield hoped their popular MP would be invited back into the party fold.

Stanfield, who is related through her husband to former Tory leader Robert Stanfield, watched in disgust last week as Harper declared the riding would have a Conservative candidate, but it wouldn't be Casey.

Stanfield, treasurer of the party's association in Truro, N.S., said she will follow Casey -- "a man who thinks with his heart" -- when he seeks re-election as an Independent candidate.

With the most recent poll showing the Tories opening a slight lead on the Liberals, each riding could put them closer to a majority government.

"It's a hard place to be right now," said Stanfield. "I've been such a party person. I have always worked for the Conservative Party."

Jeffrey MacLeod, a professor of political science at Mount Saint Vincent University in Halifax, said Harper has ignored a regional Tory culture based on accommodation and "forgive and forget."

"The fact that Casey wasn't invited back just doesn't play well in Atlantic Canada," he said.

Harper, he argues, was "more concerned with the abstract concept of party discipline over resolving this political impasse in Nova Scotia."

Still, some of the most powerful Tories in the province are staying out of the fray, signalling that Harper has retained allies as a result of the recent deal, which the premier has said could be worth about $1 billion to the province.

MacDonald, who had urged Casey and Nova Scotia's two other Tory MPs to vote against the budget earlier this year, was taking a neutral stance Monday, saying he "respects" the MP for his stance.

"I wouldn't want the federal government to get involved with respect to my caucus and the issues involved there, nor will I get involved with others and the caucus issues," he said.

Scott Armstrong, president of the Nova Scotia wing of the Conservative party and head of Casey's riding association, said he still has hopes party unity will prevail.

"Our party association has been together since 1867...Some of the last names are the same from the last 140 years," he said.

"We've asked the prime minister to reconsider. We do that respectfully. We hope he changes his mind and Bill can run as a Conservative."

In Ottawa, Ryan Sparrow, a spokesman for the Conservative party, said there is no chance that will happen.

"All I can tell you is that it's very clear. He (Casey) will not be a candidate," he said.

"With his budget vote, Bill Casey joined with (Liberal Leader) Stephane Dion in voting non confidence in the Conservative government and his Conservative colleagues. He made his choice."

A formal decision on Casey's fate and that of his riding executive will come within days, he added.

Brooke Taylor, Nova Scotia's agriculture minister, said the prime minister's approach simply isn't good for the party in the province.

"My first choice is to bring Bill Casey back into the tent, (but) that's not doable," said Taylor, a staunch Harper supporter. "So, there will be some lingering effects."