Senior Conservatives told May that if the advisors didn't go, they would mount a leadership challenge.
Like Bernie Sanders, Jeremy Corbyn has fought off critics who said he couldn't attract widespread appeal.
If the polls turn out to be true, it would represent a major embarrassment for Prime Minister Theresa May, who called the vote to try to build on her current 330 seats by a substantial margin.
The final opinion polls show a healthy lead for the Conservative Party but were badly wrong two years ago.
Deadly attacks in London and Manchester had perpetrators known to intelligence. Did tight budgets hinder security services in preventing the violence?
In 2002, Conservative candidate Peter Cuthbertson wrote in a blog that a woman's promiscuity was relevant in rape cases.
The Opinium and ComRes polls published on Saturday showed the lead of May's ruling Conservative Party had slipped to 10 and 12 percentage points respectively.
The social network is trying to tackle fake news following criticism that it allowed far-right groups to spread lies before the U.S. election.
Polls show May's Conservatives remained between 11 and 17 points ahead of Labour—still enough to deliver a clear victory as she seeks a mandate for her plan to implement the result of last year's Brexit referendum.
With some polls giving May a more than 20 point lead, the main opposition Labour Party pledged to introduce new public holidays to try to unite a country divided by the Brexit vote.
Two polls on the final day of campaigning found Labour and the Conservatives tied
Cameron's "Little England" policies do not augur well for a U.S. foreign policy which encourages like-minded states to share the burdens of leadership.
The two main parties have been neck-and-neck in most opinion polls since the start of the year, with neither establishing a sustained lead.
Labour deal with SNP would result in "mayhem" says former Conservative PM as knife-edge election race continues.
Labour leader polls 35% after debating four smaller party leaders, including SNP's Nicola Sturgeon, who got 31%.
Prominent tax expert counters Tory claims that scrapping of non-dom status would cost Britain money.
Britain's continued membership of the European Union hangs on the outcome of the election on May 7.
Miliband said he is a "resilient guy" and believes he has been underestimated.