By David Ljunggren
OTTAWA (Reuters) - Angry opposition parties are set to vote Canada's ruling Conservatives out of office on Friday and trigger an election in a risky gamble that they can claw back a widening gap in opinion polls.
But the Conservatives, in power since 2006 with two successive minority governments, are riding high. Polls show Prime Minister Stephen Harper holding onto power in an early May election and most likely strengthening his position.
"The Prime Minister and his Conservatives are in an enviable position heading into what will likely be a campaign beginning this weekend," said pollsters Ipsos Reid, which on Thursday released a survey that showed 43 percent of voters backed the Conservatives.
That is likely more than enough for Harper to win his first majority of seats in the 308-seat House of Commons and secure a four-year term in office.
The Conservatives say an election is the last thing Canadians need at a time when the economy is outshining those of most industrialized nations as it recovers from recession.
The three opposition parties say a series of ethical woes facing the government, and what they portray as its mismanagement and excessive secrecy, means Harper has to go.
Parliament votes on a motion of nonconfidence in the government at around 1:30 p.m. EDT (5:30 p.m. British time). All three opposition parties have said they will vote in favour, launching Canada into its fourth election in less than seven years.
Only two parties can realistically win the election -- the Conservatives or the main opposition Liberals -- and both stress the need for fiscal austerity and the importance of paying down Canada's record budget deficit.
The Liberals vow to scrap C$6 billion (3.7 billion pounds) in corporate tax cuts and end what they say are extravagant multibillion-dollar plans to buy new fighter jets and build prison cells.
Harper, highlighting risks to the recovery, says his opponents are treating the economy as "a political game."
Canada's budget deficit hit a record C$55.6 billion last year, but that's tiny compared to a projected $1.645 trillion (1.02 trillion pounds) U.S. shortfall in 2011. The Canadian jobless rate is 7.8 percent compared with 8.9 percent south of the border.
The opposition thinks it can benefit from a series of ethical scandals to hit the Conservative Party, which came to power in 2006 promising to clean up Ottawa.
Police are investigating allegations of misconduct by a former Harper aide, and last month, four Conservative officials were charged with violating election financing rules in 2006.
This week, a parliamentary committee slapped the government with the first contempt ruling in Canada's history, saying the Conservatives had hidden the full costs of a spending program from Parliament.
The Conservatives have responded with charges the Liberals, the left-leaning New Democrats and the separatist Bloc Quebecois are planning to form a coalition government.
The Liberals have so far skirted questions as to whether they might seek to work with other parties after the election.
(Reporting by David Ljunggren; editing by Janet Guttsman)