OTTAWA — The federal Liberal leadership drama has gone from What About Bob? to Waiting for Trudeau.

The curtain had been expected to go up unofficially Wednesday, with party brass agreeing to release interim leader Bob Rae from his commitment not to seek the job permanently.

But the show has been put on ice -- likely until the fall -- with Rae's pre-emptive decision to scratch himself from the cast of characters vying for the starring role.

That's put pressure on the only other Liberal with an indisputably high profile -- Montreal MP Justin Trudeau, eldest son of Liberal icon Pierre Trudeau -- to reconsider his initial conclusion that it's more important to spend time with his two toddlers than to traipse around the country seeking to lead a third-party rump.

Since Rae's surprise announcement, insiders close to the 40-year-old Montreal MP say Trudeau has been hit with a "tsunami" of calls and emails urging him to run. His resolve is wavering but his wife, TV personality Sophie Gregoire-Trudeau, will be a tougher nut to crack.

Trudeau, who as a child watched his famous parents' marriage dissolve under the pressure of political life, has planned a lengthy summer vacation. He and his wife are expected to take that time to reflect on the impact a leadership bid -- or worse, a leadership win, which could mean years on the road struggling to rebuild the once-mighty party -- might have on their young family.

He's not expected to announce a decision until late summer or early fall.

In one sense, that takes the pressure off other putative contenders who likely would have felt rushed into making a quick decision had Rae been freed to run and effectively launched his campaign, as initially expected, by the end of June. Few would have wanted to allow Rae a lengthy head start, notwithstanding that the marathon race won't officially begin until October, culminating in a leadership vote next April.

With Rae out, there's "no artificial panic," says one prospective candidate, predicting that no one will now declare their candidacy until September or October.

Moreover, not knowing whether Trudeau, the presumptive front-runner and acknowledged rock star of the party, is in or out makes it harder for the others to gauge their chances. Most will likely wait until his intentions are clear.

"I think if Justin is in, it does scare off a lot of folks," says Taleeb Noormohamed, a 35-year-old, multi-lingual former Liberal candidate in Vancouver who is being encouraged by some Liberals to throw his hat in the leadership ring.

"But only because I think Justin has a lot of what people want to see, somebody with profile, somebody who's going to excite, somebody who I think represents a new generation of Liberals."

That said, Noormohamed says the party needs to get past its search for the next "Messiah" and consider a host of options in a competitive, vibrant race.

For several would-be contenders, there are additional personal considerations to take into account.

Dominic LeBlanc, for instance, has been a friend of Trudeau's all his life, as were their fathers. LeBlanc, who briefly ran for the leadership in 2008 but withdrew to allow a coronation for Michael Ignatieff, is "quite likely" to run again this time but won't make a move until he knows what Trudeau is going to do, according to a source close to the New Brunswick MP.

Former MP Gerard Kennedy was endorsed by Trudeau when he ran for the Liberal leadership in 2006; the popular MP was the featured draw at a fundraiser in Kennedy's Toronto riding just last week. So, Kennedy says Trudeau's intentions will be "part of my consideration" about taking another shot at the top job.

"Justin is a friend of mine so it matters in a sense," Kennedy acknowledges.

Still, he says his own decision will be based more on whether he believes his candidacy will help force some of the fundamental changes he believes are necessary in the party.

"I don't think the shape of the race is determined by any one person, whether it's Bob not running or Justin running. At least for me personally, at the moment, it doesn't change the way I'm approaching this," says Kennedy.

Former cabinet minister Martin Cauchon says it's "no secret" he's always dreamed of leading the Liberal party and his decision whether to run this time will be "personal," not dependent on whether Trudeau or anyone else jumps into the race.

"The party is my family, politics is my passion," he says.

However, his chances would undoubtedly be effected by comparison with Trudeau, who handily won re-election in his Montreal riding while Cauchon's comeback attempt in Outremont last year was stymied by Thomas Mulcair, now leader of the NDP. Cauchon says he doesn't think his defeat "hurts at all," contending that his roots in eastern Quebec make him "the perfect guy to bring the party back" in that region.

Ottawa lawyer David Bertschi, who ran unsuccessfully in Ottawa Orleans, says Trudeau's eventual decision has no bearing on his own leadership plans. He's been travelling the country in his "four-cylinder SUV," meeting Liberals and listening to their concerns and he intends to continue doing so throughout the summer.

"My view of it has been that the Liberal party needs someone who is willing to roll up his or her sleeves and go across the country and meet people. This is going to be a marathon and who joins the race and how they join the race and when they join the race is not going to effect my decision."

Bertschi says he won't make a final decision on his own potential candidacy until after the party sets out the rules, including the spending limit for each contender, next month. He is calling for a limit of "well under $1 million."