The announcement yesterday that Industry Minister James Moore will not seek re-election is ''bad optics'' for the Tory brand but is unlikely to impact the party's prospects this fall, says political scientist Nelson Wiseman.

First elected in 2000,* the Port Moody-Westwood-Port Coquitlam MP is the latest high profile Conservative cabinet minister to drop out before the writ drops, joining Peter MacKay, John Baird and Shelly Glover.

Moore's departure coincides with a series of opinion polls that suggest plummeting support for the ruling party after a decade of rule.**

Moore said he was leaving politics to ''pursue new opportunities'' but more so to be closer to his family. His two-year-old son Spencer has a rare bone disease and recently received ''difficult'' health news, he said.

Politically, though, the 39-year-old parliamentarian insisted that he isn't leaving the Tory fold.

''While I have every confidence that Prime Minister Harper and our Conservative Government will be re-elected, and I wish I could be part of the next Conservative government, after [five] terms and 15 years in public life, and with health challenges in my family, I have concluded it is impossible for me to seek another term in office,'' he said in a statement posted on his website.

For University of Toronto political science professor Wiseman, director of the Canadian Studies program, the move comes as a surprise. Moore was widely seen as a ''rising star'' in the Conservative cabinet and was even touted within the party as a potential successor to Harper, he said.

''If he is interested in that, one of his calculations may be: is he better positioned to run for that job if he's not identified with a loss of government, which the Conservatives may very well suffer in October,'' Wiseman suggested in a phone interview. ''If anything, he sees himself as more politically marketable not being associated with a defeat.''

Fellow political scientist Gary Levy, the Bell Chair in Canadian Parliamentary Democracy at Carleton University, said he takes Moore ''at his word'' for why he's leaving politics. It's a ''big loss'' for the party, he added.

''He was one of their better ministers,'' Levy said. ''He was not one of the highly partisan ones, always getting into fights and shouting at people. It's certainly not good to lose some of your senior people -- it's not that many, but they are some of the very best ones.''

'Anything is possible'

In recent weeks, the Conservatives have taken a battering in the opinion polls, particularly following the passage of their anti-terrorism bill, C-51, which has raised concerns across party lines over civil liberties, freedom of expression and law enforcement oversight. The federal New Democrats opposed the bill, while the Liberals supported it but promised amendments if elected.

Two new polls released on Tuesday found significant NDP gains in popular support across the country. Forum Research's poll placed support for the NDP at 34 per cent, the Liberals at 28, and the Conservatives at 26. The poll had a three per cent margin of error and a sample size of nearly 1,300.

A poll by EKOS placed the NDP at 30.2 per cent, roughly tied with the Conservatives' 29.4 per cent. The Liberals sampled at 25 points. That survey had a 1.6 per cent margin of error and a sample size of roughly 3,800.

''[Moore]'s a smart guy, he sees the polls, he's making calculations,'' Wiseman said. ''The worst job you can possibly have after being a cabinet minister … [is] all of a sudden you're on the Opposition benches where you have no resources and can just pontificate self-righteously.''

Levy disagreed that opinion polls had much impact on Moore's decision or those of his predecessors. High-level cabinet ministers are unlikely to base their political fortunes on the latest polling, he said.

''You know that things go up and down,'' he said. ''I think they have problems, certainly, but I don't think they're leaving because of that necessarily.''

Both political observers agreed that whatever the cause of the departures, the loss of prominent talent doesn't help the Tory image. But it's unlikely to hurt the party significantly, they said.

''The optics are not good for the Conservatives,'' Wiseman said. ''But I don't think it affects many votes. It can affect votes in Port Moody-Westwood-Coquitlam. Moore has a high profile in B.C… but is it going to influence anybody in Red Deer, Brandon or Sarnia?

''I don't think Moore's leaving, or MacKay's or Baird's, has much effect on the election.''

The bigger question this October, as Levy sees it, is whether people have ''had enough of the Harper government'' and want to see a change of regime. On one hand, a decade in power is ''normal'' in Canada.

''But,'' he asked, ''are people mad enough to coalesce around one of the other parties or is there chance the vote will split evenly and we get another Conservative government? Anything is possible at this stage.''

** Updated June 20 at 10:33 a.m. Earlier version misstated the year Moore was first elected.

*** Updated June 21 at 4 p.m. Earlier version misstated the start of the Conservative's majority. They have led the government for a decade but partly in minority.