Assembly of Ontario, was in the riding of Hamilton East, caused by the untimely death of the riding's MPP, Dominic Agostino, on 24 March 2004. This tragic event, in conjunction with a recent and unpopular tax increase by the Liberals, provided the NDP with an opportunity to regain party status. A by-election was called for 13 May 2004, in which the new Liberal candidate, Agostino's brother Ralph, was challenged by NDP candidate Andrea Horwath, a Hamilton city councillor. In a fight for its political life, the NDP ran an all-out campaign to win the seat, aided by the city's large base of unionized steelworkers. On election night, Horwath took 63.8 per cent of the vote in the seat, bringing the NDP back to eight seats in the Legislature and allowing them to regain official party status. The Ontario NDP's representation in the Legislature was again reduced to seven seats when Marilyn Churley resigned her seat to run in the 2006 federal election. However, the Liberals reversed their position and declared that the NDP would retain party status even if they lost the upcoming Toronto—Danforth by-election. Some opposition sources believed the Liberals, mindful of their humiliating defeat to Horwath, had loosened their interpretation of the rules so that whoever ran for the NDP in Toronto—Danforth couldn't use the threat of lost status in a campaign. This issue became moot when, on 30 March 2006, NDP candidate Peter Tabuns won the by-election in the Toronto—Danforth riding by a 9% margin over the Liberals' Ben Chin, alleviating another party status crisis. The NDP scored a surprise victory over the Liberals in the late summer of that year in the riding of Parkdale—High Park. Liberal Education Minister Gerard Kennedy resigned on 5 April 2006 to run for the Federal Liberal Party leadership. The government took an unusually long time to call the by-election, waiting until 16 August to drop the writ. It turned into one of the most vicious elections in recent Ontario memory, almost on par with Jolliffe's 1945 "Gestapo" campaign. This time though, the NDP were not making the accusations; NDP candidate Cheri DiNovo's credibility was put to the test by what most of the media considered to be unworthy and underhanded personal attacks launched by the Liberals. The tactic backfired; on 14 September 2006, DiNovo defeated Liberal candidate – and incumbent Toronto city councillor – Sylvia Watson by taking 41% of