If Barack Obama was hoping for a last-minute helping hand from the US Federal Reserve, Ben Bernanke may just have put paid to that prospect.

To have any chance of jolting America’s stalled economy before November, the Fed would need to embark on another round of asset buying – or something equivalent – at its next meeting in 10 days. But in his testimony to Congress this week the Fed chairman hinted it would probably need more time before deciding on further steps.

Mr Obama’s die is almost certainly cast. With just over 100 days before the election, the president will go to the polls in an economy stuck somewhere between recovery and double-dip recession. It is hard to imagine it could get any murkier. Yet, as Mr Bernanke implied, it is highly unlikely visibility will suddenly improve. In addition to the Damoclean sword hovering over the eurozone, Washington’s self-imposed “fiscal cliff” has cast another long shadow over the US economy.