Their fingers may be crossed, but any hope they might have is being trumped by politics and math.
They realize an increase in aid spending is unlikely, because foreign aid isn't known as a vote-getter in an election year.
A five-year freeze on development spending is supposed to end in 2015, which has aid groups anticipating the budget.
The government also cut another $378 million in foreign aid in 2012.
An Oxfam Canada official says the government has enough money to restart aid spending, but she's not holding her breath.
"We are confident there is money for this," said Caroline Marrs, Oxfam Canada's gender programs director.
"But we are not confident the government will choose to invest the money that is available in aid spending, based on seeing cuts to aid every year for the past four years."
Another Canadian aid agency official, who spoke on condition of anonymity because they did not want to be seen to be criticizing the government, said the expected October federal election makes it unlikely the government will boost foreign aid spending.
"All politics are local, and they've got very little money to play with," said the official, citing the recent slump in oil prices and the government's recent commitments to maternal, newborn and child health initiatives.
Prime Minister Stephen Harper has committed $3.5 billion toward the cause, his signature aid initiative. Last year's five-year commitment to 2020, aimed at reducing the number of deaths of newborns and their mothers in the developing world, has earned him widespread praise.
But as the Paris-based Organization for Economic Co-operation and Development said in its most recent annual analysis of international aid spending, Canada overall commitment to overseas development assistance is plunging towards record lows.
The OECD said Canada's aid spending dropped to 0.24 per cent of GDP in 2014, down from 0.27 per cent the previous year, one of the country's lowest rates in more than a decade.
The parliamentary budget officer has also documented the so-called lapsing of hundreds of millions of aid dollars that had been earmarked by Parliament for programs in poor countries. When projects sit unapproved on a minister's desk past the expiration of the fiscal year, the money is lost to the department and returned to the central treasury where it can be used to pay down the deficit.
The aid official said it could be a result of sheer incompetence, but given that Veterans Affairs has lapsed more than $1 billion in funds, it raises legitimate questions about whether the practice is part of a grander plan to find savings.
"It could be this master strategy, and God knows it seems to be something that's happened in different departments, like Veterans Affairs."
Marrs said lapsed funding makes Canada's "already meagre aid budget" look even worse.
"It is not accountable — the budget, once passed in Parliament, is a covenant of sorts with the Canadian people," she said. "When funding lapses, that covenant is broken. It also goes against Canada's OECD commitments."
The lack of an aid increase in Canada means "more children will go hungry, more women will die in childbirth, fewer villages will have access to clean water and essential medical services," said CARE Canada president Gillian Barth.
Lapsed funding only makes things worse, she added.
"Any reduction in aid or non-disbursement of available funds has real, tangible repercussions for vulnerable populations."
A spokesman for International Development Minister Christian Paradis said Friday he didn't know whether Tuesday's budget would contain an aid spending increase.
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