Just seven weeks after the prime minister's party won reelection, the Conservative administration could be toppled.
Premier Harper is favored in Tuesday's vote, but slipped in polls over economic woes.
The ruling Conservative Party hopes to win at least 30 more seats to secure a House of Commons majority.
On Tuesday, a US Army deserter was deported. An unrelated but simultaneous video release showed a Canadian Gitmo detainee taken at age 15 crying, 'Oh Mommy!'
A look at environment stories elsewhere on the Web.