Image caption The September figure was hailed by campaign managers as the most successful month so far

A record $181m was raised in September for US President Barack Obama's re-election bid, officials say.

"This is by far our biggest month yet," said campaign manager Jim Messina in an email to supporters.

No September figures for Mr Obama's Republican rival are available yet. Mr Obama narrowly beat Mitt Romney in the August fundraising totals.

The figures are a boost for Mr Obama, under fire for his performance in the first presidential debate on Wednesday.

They come a day after figures showing that unemployment in the US in September fell to 7.8%, its lowest rate since January 2009.

Mr Messina said that September's total of $181m (£112m; 138m euros) in donations came from 1.8 million Americans, more than a third of whom were donating for the first time.

Reuters news agency says that while President Obama's total for September was the biggest monthly haul so far this time round, it was lower than his September figure four years ago, when the combined Democratic fundraising effort netted $193 million.

In August, the Obama team and Democratic supporters raised more than $114 million, just ahead of $111 million for Mr Romney's campaign.