McCain Quits in Michigan

John McCain conceded a crucial battleground to Barack Obama yesterday, pulling staff out of Michigan to try to shore up his campaign in other states.

The first big battleground state to be surrendered by either candidate marks the most concrete acknowledgment to date from the McCain camp that the Republican was losing ground because of the economic turmoil and the $700bn bail-out of Wall Street.

"The winds that drive presidential campaigns can shift and shift suddenly. I have no doubt the campaign will be back," the Republican state party chairman, Saul Anuzis, said.

Campaign officials told a conference call that resources would be moved to the battleground states of Wisconsin and Pennsylvania as well as Maine, which had not been thought to be in contention.

"If we see a swing back in our favor, we will re-engage," said Mike Duhaime, a Republican strategist.

But Republicans acknowledged that the retrenchment in Michigan would make it more difficult for McCain to put together a winning combination.

The abrupt decision follows a striking rise for Obama in local opinion polls and an aggressive push by Obama, who spent four hours in the state yesterday, holding a rally in the Republican enclave of Grand Rapids.

The Democrats plan to focus on North Carolina next week as Obama stays there to prepare for his second presidential debate against McCain.