Libs wary of McGowan

State Liberal MPs have been warned that Mark McGowan's elevation to the Labor leadership is a "game-changer" and they should not be complacent in the lead-up to the March 2013 State election.

Liberal MPs gathered in Albany late last week and at the weekend for a "love-in" ahead of the new parliamentary year, which begins a week tomorrow.

Sources said the message from Premier Colin Barnett and party State director Ben Morton was that MPs could not afford to be complacent. "Mark McGowan is a game-changer," one MP said.

"The polls will narrow as we get closer to an election and he (Mr Morton) was sending the message not to get complacent. It's anything but over. It's a different election now and McGowan is a far more energetic leader than Eric Ripper.

"I would say that the level of caution (among Labor MPs) has increased. We are all aware that it will be a tougher election."

Murray-Wellington MP Murray Cowper will be the only sitting WA Liberal MP to face a challenge to his seat from within his own party after Shire of Waroona executive Stephen Cleaver nominated to run against him.

Mr Cleaver, 42, Waroona's director of community and planning services and a member of the local Liberal Party branch, will take on Mr Cowper, who has represented the electorate since 2005.

The seat is held by the Liberals by a notional 8.8 per cent under the updated electoral redistribution.

Mr Cowper said he had no problem with a challenger.

"Any member of the Liberal Party is able to nominate for any position," he said.

"I think it's healthy that we have a system that allows the membership to put the ruler over the people from time to time.

"I'm quite comfortable with the work I've been doing in the electorate. I've taken it from a Labor seat, to a marginal seat, to a reasonably safe seat and I suppose it's become attractive."

Asked if he was confident of winning the nomination, Mr Cowper said: "I suppose it comes down to the membership. We're a democratic party, we don't anoint people."