John McCain’s campaign team sought on Wednesday to shut down persistent questions on how thoroughly the Republican presidential candidate had vetted his running mate, Alaska governor Sarah Palin.

The campaign made a bid to regain control of its message hours before Ms Palin was due to address the Republican National Convention by lambasting a flurry of reports suggesting Mr McCain had minimal knowledge of the governor before choosing her as his vice-president. The campaign said the reports were nothing but a “faux media scandal designed to destroy the first female Republican nominee”.