One of Stephen Harper's closest advisers is being sent back to Ottawa after a series of missteps knocked the Conservative leader's re-election bid off message, CBC News has learned.

Conservative campaign manager Jenni Byrne, who has been travelling with Harper, is returning to Ottawa.

Sources tell CBC News she is bearing the brunt of Harper's anger over this week's decision to boot two candidates who made it through the party's screening process, which she was supposed to oversee.

One of those candidates had been recorded on tape urinating into a mug while on a service call at a private home, while the other was removed for making prank calls recorded on YouTube that mocked people with disabilities.

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Jenni Byrne, seen at a Stephen Harper campaign stop in Toronto in August, has been sent back to Ottawa. Tories say it's an effort to refocus a campaign overtaken by events. (Sean Kilpatrick/Canadian Press)

Other parties have also had problems with candidates: The Liberals are looking into online tweets posted by an Alberta candidate who posted slurs against women on Twitter, while a senior aide to New Democrat Leader Tom Mulcair  apologized on Tuesday after past tweets surfaced in which he took aim at the Roman Catholic Church.

But Conservatives sources say the decision to send Byrne back to Ottawa is part of an effort to refocus the campaign after weeks in which their message has been overtaken by other events.

They include allegations coming from the Mike Duffy trial that a number of key members of Harper's inner circle knew that his former chief of staff Nigel Wright had repaid $90,000 in Duffy's expenses, as well as Harper's insistence that Canada will not expedite the resettlement of Syrian refugees fleeing in the tens of thousands from the violence in their home country.