Tory MPs point to next month's Queen's speech: how he performs in his response to it may prove to be a decisive "tipping point" as to whether he can stave off the speculation about his position.

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It may even prove decisive to the viability of the All Volunteer Force.

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He admitted the project had still not reached its "tipping point", but said if the EAC was successful it may prove to be the decisive moment for the project.

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There is, however, another test that may prove even more decisive to the prospects for providing the American people with the sort of protection they expect and deserve: Will the four uniformed leaders of the Nation's armed forces be allowed to play a substantive and influential role in decisions that appear likely to preclude the development and deployment of effective national missile defenses?

CENTERFORSECURITYPOLICY: Center For Security Policy

Second, the 1.5m Muslims in England and Wales are not numerous enough to shape the overall result, though their votes may prove decisive in a small number of constituencies such as Leicester South, which the Liberal Democrats took in a by-election last year.

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It ultimately has the power to choose whether to let her stand as Labour candidate or to de-select her but the verdict of the NEC could prove decisive.

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The campaigns concentrate on them because they are the voters most likely to change their minds and, with the candidates neck-and-neck, may prove decisive this year.

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