sentences:  Thatcher's former cabinet colleague Michael Heseltine then challenged her for the leadership of the party; she led the first round of voting by Conservative MPs (20 November) with just under 55% of the vote, but fell four votes short of the 15% margin needed to win outright.Though she initially stated that she intended to contest the second ballot, most of Thatcher's Cabinet colleagues offered her at best lukewarm support and many warned her that she would very likely lose a second ballot to Heseltine.On 22 November, at just after 9.30 am, she announced to the Cabinet that she would not be a candidate in the second ballot after all.