President Barack Obama’s approval rating has hit a new low as Americans disapprove of his policies on the economy, health care and the crisis in Ukraine, according to a new poll.

Obama’s rating sunk to 41 per cent from 46 per cent in the first three months of the year, according to the Washington Post-ABC News poll released late on Monday in a worrying sign for allied Democrats facing legislative elections in November.

Only 42 per cent of those polled approve of his handling of the economy, 37 per cent agree with how he has handled implementation of the new health care law known as Obamacare and 34 per cent approve of his stewardship of the crisis involving Ukraine and Russia, said the poll.

The president’s low numbers could hurt Democratic candidates this year.

Previous elections suggest that when presidential ratings are as low as current levels, his party is almost certain to take a hit from voters, the Post said.

Republicans now control the House of Representatives and are expected to retain that majority. So the focus is on whether they will also seize the Senate from the Democrats.

Turnout is key. In US mid-term elections, it tends to be lower than in presidential elections.

And now key components of the Republican base – white voters and older voters – say they are more certain to cast ballots this year than are younger voters and minorities, the Post said.

Obama relied on the latter to win election in 2008 and 2012.