LONDON -- By the end of today, British Prime Minister Margaret Thatcher could be on her way to being simply Margaret Thatcher, M.P. But, then, maybe not.
The political future of Mrs. Thatcher, for more than a decade the dominating force in British politics, rests in the hands of 372 Conservative Party members of Parliament, who today vote on whether to keep her as leader of their party and, by implication, as prime minister of the United Kingdom.
The choice is between Mrs. Thatcher and her former Cabinet minister, Michael Heseltine; between the familiar old and the flamboyant new; between the prime minister's combative attitude toward Europe and her challenger's more conciliatory approach.
Mrs. Thatcher, in Paris for a meeting of the Conference on Security and Cooperation in Europe, said that she "most earnestly" believed that she would still be in Downing Street at the end of this week "and a little bit longer than that."
President Bush, also in Paris, did her chances no harm when, after a breakfast meeting with her, he told a news conference: "We have a superb relationship with Mrs. Thatcher. It is indeed a special relationship."
Mr. Heseltine, meanwhile, took heart from five polls taken over the weekend. Each showed a dramatic rise in the popularity of the Conservative Party if Mr. Heseltine were elected leader. It may be enough to persuade wavering Conservative lawmakers, mindful that a general election must be called within 18 months and that they have long trailed Labor in the polls, to switch allegiance to Mr. Heseltine.
To be elected leader today, a candidate needs 214 votes. If no one wins outright, the vote will go on to a second ballot. Other contenders may then enter the fray, and Mrs. Thatcher may be persuaded to drop out and let her popular Cabinet colleague, Foreign Secretary Douglas Hurd, put forward his name.
Lawmakers returned to Westminster yesterday after spending the weekend testing the public mood in their local constituencies. Many were refusing to divulge their voting intentions, making accurate prediction of the result difficult. But an insider at Parliament said that the mood was "overwhelmingly pro-Thatcher."