And in a sharp, online rebuke of his caucus, Alberta MP Brent Rathgeber is airing a complaint other Tory MPs say they're also hearing about on the doorsteps this summer: that the government is wasting people's money.
Rathgeber reports he was in Grenfell, Sask., a town of around 1,000 people last month, and found that the champagne tastes of senior Tories were at the top of people's minds.
In May, CTV revealed that more than half a million dollars in overtime was paid to ministerial drivers and some remained on standby almost all year long.
"The $600,000 in limousine driver overtime did not play well with the small prairie town sensibilities," Rathgeber wrote on his blog. "How could the average payout be $20,000 and how could the chart-topping minister's driver rack up $40,000 in overtime charges?
"Admittedly, I had no answers. The cabinet minister limousine service represents one of the most egregious displays of Ottawa opulence."
Rathgeber, who represents the riding of Edmonton-St. Albert, wrote that he understands why ministers need to be driven around Ottawa, but doesn't understand why they need such expensive car service while on Parliament Hill.
"Surely there is a more cost-effective method of getting cabinet ministers to and from meetings," he wrote.
"Surely, as government preaches fiscal discipline, such extravagance must be eliminated."
In the House of Commons, the government has defended the cost of cars and drivers.
"Our ministers are working long hours for the economy, long hours for jobs, long hours for the people of Canada," Treasury Board President Tony Clement said at the time.
"Sometimes that means a bit of overtime by the drivers."
The government is reviewing the rules, though a spokeswoman for Clement noted that the issue of overtime and salaries are governed by union agreements.
The story on driver costs followed revelations by The Canadian Press that International Co-operation Minister Bev Oda spent $16 on a glass of orange juice at a hotel and $1,000 a day on limousines during a 2011 conference in London.
Rathgeber noted that Oda apologized and repaid the money but suggested people may not be forgiving.
"In Grenfell, most of the attendees have never ridden in a limo and none of them have ever drunk $16 orange juice," he wrote.
"Surely, they would appreciate if government took more care in spending their money."
In an interview, Rathgeber said he was airing a complaint he's also hearing in his own riding.
"We all have a job and my job as a member of Parliament and as a member of the Conservative caucus is to hold the government to account, even though I am a member of the government caucus," he said.
"I still think that I have a responsibility to do what I can to ensure taxpayers get value for their dollars."
His blog was posted as Conservative cabinet ministers, parliamentary secretaries and MPs fanned out across the country to plug the government's budget bill at a series of events Tuesday.
Rathbeger said he knows the money spent on drivers wouldn't make a dent in the deficit.
"It's an issue I guess of optics, and it's an issue of leadership," he said.
"At a time when we are attempting to get our fiscal house in order and we're asking Canadians to make some sacrifices, with respect to government programs and services that are offered, I think it's incumbent upon politicians to do the same."
Complaints about Oda's expense claims have found their way into caucus meetings since the story broke in April.
MPs are concerned about further blowback from Canadians if the minister isn't replaced in a widely expected cabinet shuffle this summer.
Since 2006, Harper has been expanding the size of his cabinet, which in turn increases its cost.
In 2011, the bill for salaries and perks for him and the other 38 ministers and junior ministers was about $9 million, the highest on record.
Ontario Tory MP Rick Dykstra said he, too, has received an earful about Oda's spending and cabinet cars in the last few months.
But he said the budget is prompting questions as well and not the kind he's used to hearing.
Ever since he's been back in his St. Catharines, Ont., riding, Dykstra said he's received a "boatload" of queries on the marathon voting session in the Commons earlier this month, when MPs voted continuously for almost 24 hours on hundreds of opposition amendments to the budget bill.
"It's very rare when I get constituents actually talking to me about what's happened in the House of Commons, actually in the House itself," Dykstra said.
Rathgeber is the latest backbencher to pop his head over the wall of silence that usually keeps Tories from public criticism of the government.
Earlier this month, Nanaimo-Alberni MP James Lunney spoke out against planned cuts to coast guard services being made as part of the government's overall drive to slash spending.
And in May, another B.C. Tory, David Wilks, raised concerns about the budget and the lack of say backbenchers have in overall government policy.
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