Ontario Liberals pick a new leader this weekend, and no one is more anxious for the result than their federal party cousins.

It's easy to understand why.

The once mighty federal Liberal party is the poor cousin these days. Out of power, out of favour. And out of the limelight.

And nowhere is that more problematic than in the country's largest, most vote-rich province, where the race to succeed Premier Dalton McGuinty has received far more attention, and drawn in far more key organizers than the federal leadership campaign.

Oh. One more thing. It's also the contest with the highest stakes.

The winner this weekend becomes Ontario's next premier, and she (OK, it could be he) will head a minority government with a potentially short lease on the corner office at Queen's Park.

For federal Liberals, the prospect of a provincial election before the spring has even sprung, and before the federal Liberals can choose their own new leader on April 14, ranks among the worst-case scenarios.

For them, a priority in the weeks ahead is to ensure the interests of the party's two branches align.

A brand in decline

The to-do list for both parties begins with simply re-establishing the Liberal brand.

Federally, the Liberals have been in steady decline since 2004, when they went from being a three-term majority government to minority government, to Official Opposition and now third-party status in the House of Commons.

During that time the party has had four leaders, seen its popular support fall below 20 per cent nationally, and seen its stranglehold on Ontario's federal ridings eroded by both the Conservatives and the New Democrats.

The causes are, of course, well documented. From the sponsorship scandal in Quebec, to a lack of clear policy options, which prompted Toronto Star columnist Thomas Walkom to write this week that, "As a party, the Liberals haven't had a new idea since the 1980s.''

It's a harsh assessment. But there's a great deal of truth to the argument that the Liberals failed to establish themselves as a viable alternative to Stephen Harper's Conservatives, and in the process ceded turf to the NDP that they have yet to recover.

And underneath it all rests a nagging suspicion among too many voters that the party simply fell out of touch with them amidst the many rounds of internal leadership battles in Ottawa.

Bastion Ontario

By comparison, the Ontario Liberals appear to be doing just fine.

Dalton McGuinty formed back-to-back majority governments in 2003 and 2008, and then snatched a slim minority government in 2011.

Along the way, he made considerable strides in improving the province's schools, and reducing hospital wait times.

Plus, he made the bold political calculation that harmonizing the provincial sales tax with the dreaded federal GST would be good for Ontario, and by most accounts he was proven right.

Supporters put up posters Thursday for Sandra Pupatello, one of the front-runners in the Ontario Liberal leadership. Almost all the contenders have had significant cabinet experience. (Frank Gunn / Canadian Press)

In the process, McGuinty proved, much to the chagrin of federal Liberals, that he could work with Stephen Harper on specific projects, right up to this week when the two leaders pledged millions of dollars to help build a hybrid car in Cambridge.

But his legacy also includes a drawn-out departure precipitated by the whiff of scandal involving an election about-face; and an unresolved, simmering labour dispute with the province's teachers, once a bedrock of Ontario Liberal support.

It's not a great gift to leave your successor. But even so, the challenges facing the next Liberal premier are far less daunting than the ones the next leader of the federal Liberals will confront.

The Ontario party remains in power, having missed a third straight majority by a single seat. Party memberships doubled in the leadership race that's both close, and comes with an appealing sub-plot.

The two frontrunners heading into Saturday's vote are women — Sandra Pupatello and Kathleen Wynne — and the odds are that one of them will make history Saturday by becoming Ontario's first female premier.

On the federal side, meanwhile, there's only one frontrunner.

Justin Trudeau is brash, youthful and almost entirely lacking in political experience.

He's got the famous last name, and these days that alone carries an enormous amount of weight in a party that's seen some very lean years on the national stage.

But whoever wins the federal leadership in April will have to start the hard work of re-building in Ontario, where the party now holds just 11 of the province's 106 seats.

It's a job that will be made much easier if there's no competing agenda in Ontario — let alone an actual election this spring — that could make for awkward moments.

Liberals from both camps expect the new premier will play for time, to build some much-needed distance from the McGuinty years, and to convince voters that this is a new and different Liberal government.

It's a position their poor cousins in Ottawa would appreciate.