我要求助 翻译, 如何, political, becoming, become

雨落风残

But none of his rivals will be under the microscope — or wearing as large a target — as Mr. Perry. In three short weeks since becoming a candidate, Mr. Perry has become the new front-runner and the media focus on his record and his comments has robbed the other candidates of political oxygen.

红色部分如何翻译才正确? 是短短三个星期，还是不足三个星期？