A grass-roots political party appears the biggest beneficiary of a drop in support for the Democratic Party, the latest University of Hong Kong ranking of political groups' popularity shows. Support for the moderate Association for Democracy and People's Livelihood was up 2.7 points last month on its showing in April, with the party scoring 50.1 points out of a possible 100. The Democratic Party's rating dropped 1.6 points to 47.4 points amid controversy over legislator James To Kun-sun's claim for reimbursement of above-market rent on a party office he part-owned. The Democratic Party's score in the survey dropped below that of arch-rival the Democratic Alliance for the Betterment and Progress of Hong Kong for the first time since November 2002. However, both the Democratic Party's declining score and a 1.2 point rise for the DAB, to 47.7 points, were within the survey's margin for error. Robert Chung Ting-yiu, director of the University of Hong Kong's public opinion programme, said the rent affair was the reason for the Democratic Party's slide. Party chairman Lee Wing-tat said it would work harder to improve its support base. 'It's important that we step up our efforts on democracy and people's livelihoods,' he said. The pro-democracy Article 45 Concern Group remains the most popular political party, according to the survey.