The minority Liberal government of Prime Minister Paul Martin is fighting for its life.

"They just want to make it to June 23," Robert Fife, CTV's parliamentary bureau chief, told CTV.ca.

However, the opposition parties are scheming to bring the government down before then.

While Martin has promised he'll call an election within 30 days of the Gomery Commission filing its final report, which might not happen until December, at present the prime minister does not control his government's destiny.

The people who can collectively force him from power are Conservative Leader Stephen Harper, Bloc Quebecois Leader Gilles Duceppe, NDP Leader Jack Layton and the three independents: Chuck Cadman, Carolyn Parrish and David Kilgour.

Here are the numbers:

• Liberals: 131 plus the Speaker
• Conservatives: 99
• Bloc Quebecois: 54
• NDP: 19
• Independents: 3
• Vacant: 1

The magic number is 154. If 154 MPs vote against the government on a motion of confidence or a key bill such as the budget, the government collapses and Canadians are into their second federal election campaign within a year.

There are two likely ways the government will fall: On a non-confidence motion or in the defeat of the budget.

The budget

Finance Minister Ralph Goodale delivered his budget speech on Feb. 23.

There were a series of votes on amendments to the budget on March 7 and 8. Those were voted down. On March 9, the budget was approved in principle, with the NDP and Bloc voting against it and the Conservatives abstaining.

In normal times, that would end the matter.

But since then, the government has been politically wounded by allegations of sponsorship program corruption coming from witnesses testifying at the Gomery inquiry.

A vote on a budget is a matter of confidence in the government. If the House of Commons votes down a government's budget, then it's time for Canadians to choose a new government.

While Parliament may have approved the budget in principle, there's still the legislation required to enable it, Christina Van Loon, press secretary for Government House Leader Tony Valeri, told CTV.ca.

The bill is called C-43:  "An Act to implement certain provisions of the budget tabled in Parliament on February 23, 2005."  The bill passed first reading on March 24. Van Loon said the bill is currently in second reading before the House (which is in recess until May 2).

The next vote is the second reading vote.

Asked if the bill was close to becoming law, Van Loon said, "It depends how quickly the parties want to move it."

The next vote will depend on when the parties finish debating. "It's difficult to predict. We're anticipating in May, but when in May, I couldn't tell you," she said.

NDP Leader Jack Layton and Martin have been negotiating over NDP support for the budget.

The Liberals and NDP together don't have enough votes to pass C-43 without support from all three independents.

And then there's the threat of a regular non-confidence vote.

Non-confidence motions

In a Parliamentary system, the government rules with the confidence of the House. If you have a majority government, that's easy.

Back in the 1970s, the minority government of Pierre Trudeau needed only the support of the NDP to govern.

These days, Martin must hope the Conservatives and Bloc don't simultaneously decide to defeat him, because they almost have the votes to do it.

Once the Gomery revelations heated up, the Bloc had planned to move a non-confidence motion on April 14. That day was designated a so-called opposition day. Such days allow opposition parties to have some influence on the legislative agenda. There are seven of those days per session.

In that case, the Bloc backed off when the NDP and Conservatives wouldn't support its motion.

On April 18, a huge fight erupted over the control of opposition days.

Valeri announced he was pulling an opposition day scheduled for April 20. The minister said he had found out the Conservatives would move a motion trying to regulate when opposition days would be held.

All the opposition parties exploded at this. The Conservatives claimed the government wanted to push all the opposition days to the end of the session.

This led to the following sequence of events:

• April 19: A motion was moved and passed at a Commons Procedures and House committee meeting calling for May 19 to be designated an opposition day.
• April 21: The public accounts committee passed a non-confidence motion that could lead to a vote as early as May 3.
• April 22: Stephen Harper moved another non-confidence motion.

While the rules of Parliament are complex, the important thing to remember is the full House can now vote on committee motions.

Fife said the reason for all the motions was simple: "They're trying to create a number of opportunities where they can bring down the government."

The government can use the procedural rules to delay, but by May 18 to 19, there will likely be a non-confidence motion that will lead to a June 27 election call, he said.

If that motion is successful and the budget isn't passed by then, then the budget -- and any other unpassed legislation -- gets tossed in the recycling bin.

The NDP support for the budget might only help the government survive another week. Layton has offered no guarantees of support for the government against a non-confidence motion.

And if the Liberals give up too much in trying to win NDP support, they risk a backlash from other supporters.

Welcome to politics.