OTTAWA -

The Conservative campaign caravan sought to steer itself back on course Thursday with a long-term tax pledge, a pile-on against a Liberal foe and, finally, a clear apology from Prime Minister Stephen Harper.

That combination of tax policy and raw politics helped the Tories regain some control Thursday after several days of having their campaign message repeatedly sidelined.

And they hope the formal release of their platform on Friday in Mississauga will tighten their grip on the reins.

Already, they have promised to eventually double to $10,000 the maximum annual contribution to Tax Free Savings Accounts once the deficit is eliminated in 2015. TFSAs allow people to save money, including investment dividends, without being taxed; the Tories estimate 4.7 million Canadians have one.

The time horizon on that promise is so distant, however, that the Liberals likened it to promising beer out of rain water.

The policy also has other possible drawbacks. It will be of little use to Canadians unable to save more than $5,000 per year, while leaving a permanent multibillion-dollar dent on federal finances.

Friday's platform will focus on five priorities: creating jobs, supporting families, eliminating the deficit, getting tough on crime and investing in the North.

Much of it reflects initiatives from the failed March budget which will be resurrected.

But there will be some smaller carrots as well, including a pledge to install defibrillators in every arena in the country.

The Conservatives also launched a Twitter blitz Thursday to draw attention to a Liberal candidate's remark in a radio interview that some types of sexual assault -- like inappropriate touching -- don't merit equal jail time.

That offensive against John Reilly, a former judge running for the Liberals in Alberta, came after a week in which the Tories were forced to play defence, with several of their own members undermined by mischief-making from opposition researchers.

Also Thursday, the prime minister finally said sorry.

After three days of controversy, Harper apologized for several recent incidents in which people linked to rival parties were kicked out of Tory campaign events.

"If anybody is kept out of any of our events that's there to hear our message, then we obviously apologize to them," Harper said during a stop in Vaughan, Ont.

"Our interest is in having as many people out to hear our message as we can."

As if on cue, a group of McMaster University students who showed up in a so-called flash mob outside Hamilton Convention Centre were allowed in to Harper's Thursday night event.

A pair of protesters clad in chicken costumes, however, were not.

Harper's apology came after the RCMP admitted its officers had been helping the Tories eject people -- a role the Mounties have, over the years, occasionally been forced to play at Conservative events. The force reminded its officers this week that they should only be guarding leaders, not serving political parties.

Michael Ignatieff seized on the opportunity to compare Harper's campaign style to his own. The Liberal leader said he routinely mingles with members of the public, risking the occasional encounter with insults or indifference.

"What is this? Canadian democracy," he said in Laval, Que. "I've tried to run a campaign where we don't do identity checks, we don't do Facebook checks. We say, 'Come on in!' "

Ignatieff started his day at a seniors' residence, where he outlined promises to improve the pension system.

But afterward, he faced a number of uncomfortable questions, such as how he plans to pay for his campaign promises.

Ignatieff has denounced the government for wasting resources on fighter jets and bigger prisons when the priorities of Canadians lie elsewhere. However, he hasn't offered much detail on what alternatives the Liberals would offer.

The Conservatives have been pushing, with little success, for an explanation of which crime legislation Ignatieff might strip down in order to save money on penitentiaries.

The Tories also worked to spoil the day for Ignatieff and his candidate from Alberta's Wild Rose riding.

Reilly, a former provincial court judge, suggested in a radio interview that not all types of sexual assault should result in jail time. The Tories took to Twitter -- from the campaign co-chair all the way to grassroots supporters -- to spread word of Reilly's remarks.

A full transcript of the remarks later made clear Reilly was describing a case where a young man faced a possible three-year prison term for inappropriate sexual touching of his teenage girlfriend at a party.

The Conservatives released one inflammatory snippet from Reilly's interview -- "well, you know, there are sexual assaults and there are sexual assaults" -- but left out much of the exchange.

The anecdote about the teenagers was part of a broader discussion where Reilly ripped into the mandatory minimum sentences that are a cornerstone of Conservative justice policy.

Nonetheless, the Liberals were clearly keen to escape that debate.

Reilly immediately apologized for what he called a "clumsy example" and stressed that all sexual assaults deserved punishment. The Liberal leader denounced the comment as "disgraceful" and "utterly, totally unacceptable."

However, Ignatieff -- who the previous day dumped a northern Quebec candidate who had made derogatory remarks about natives, Muslims and gays -- stopped short of banishing Reilly, citing his long and distinguished public record.

"(Reilly) has served the community with a long record of distinguished public service," the Liberal leader said.

"He made one remark that he's going to regret for the rest of his life. He's offered an unreserved apology. I've accepted it."

The NDP was also talking about crime Thursday.

Leader Jack Layton promised to put an additional 2,500 police officers on streets across the country and double funding for programs that try to keep children from joining gangs. The NDP says it would spend $250 million a year on a suite of crime-prevention programs and additional police.

On the legislative side, Layton said the NDP would make gang recruitment illegal. It would also make car-jacking and home invasions separate offences under the Criminal Code. He made the announcement in Surrey, B.C., where violence among young people has skyrocketed.

Harper spent the morning campaigning alongside his party's most prominent voice for law and order -- former Ontario police chief Julian Fantino.

The gruff ex-cop, an ardent critic of Liberal crime policies, revealed another thing he found mystifying in his few months as an MP in the House of Commons: members of the Bloc Quebecois, who want to separate from Canada, apparently don't participate in the weekly singing of the national anthem.

"I find that very strange," Fantino said.