Ukip has maintained its recent surge and now commands 20% of the national vote, according to the latest Observer/Opinium poll.

Nigel Farage's party is now just nine points behind the Conservatives with less than a fortnight to go before council and European elections.

Labour, on 33% (-1 point compared to a fortnight ago), has stretched its lead to four points lead over the Tories (who are down three points). Low scores for both the main parties suggest Ukip (up two points) is draining votes from the two biggest established parties. The Lib Dems are up two points on 9%.

Ukip's score of 20% is its highest since last summer's Opinium record of 21% and suggests voters have not been deterred in large numbers by a series of gaffes and claims that some of its members are racists.

Opinium also asked a series of questions about voters engagement with and knowledge of the EU. Only around one in 10 (11%) said they were confident they could name one of their regional MEPs, compared with 52% who believed they could name their local MP and 31% who could name one of their councillors.

If voters' ability to name their MEPs was poor, engagement with their EU representatives is even lower. Just 8% of UK voters have ever contacted one of the MEPs, while 79% have never even considered approaching one of their MEPs.

Some 27% of voters correctly named José Manuel Barroso as president of the European Commission, and 23% correctly identified Herman Van Rompuy as president of the European Council. Almost one in five (19%) thought, however, that Angela Merkel, the German Chancellor, was president of the European Commission.

Views on the importance of the European parliament were mixed: 43% said it was important to the way the UK is governed, while 37% said it was not.

Voters were also asked about their view on coalition government after four years of joint Tory/Lib Dem rule.

There was strong single-party government support, with 55% saying it is better for Britain, compared with 15% who prefer a coalition.

In the event of no single party winning a majority, however, only 18% of voters said they thought the largest party should form a minority government. Some 35% thought a coalition would be better while 30% believed another election should be held.

Ukip's score of 20% is its highest since last summer's Opinium record of 21% and suggests voters have not been deterred in large numbers by a series of gaffes and claims that some of its members are racists

Opinium Research carried out an online survey of 1,997 UK adults from 7 to 9 May 2014. Results have been weighted to nationally weighted criteria.