Rennard served as the Liberal Democrats Chief Executive from 2003 to 2009, during which time he was in overall charge of the party's election campaigns and organisation. His campaigns team continued to build the party's successes through by-elections such as Brent East in 2003 and Leicester South in 2004. Following the Lib Dems' victory at Brent East in 2003, "The Independent" profiled Lord Rennard, saying calling him "a Liberal democrat who knows how to win elections" and saying that "In recent years thoughtful Conservatives surveying their wretched political predicament sometimes wondered aloud where "their" Peter Mandelson was. As usual they were asking the wrong question. They should have been seeking "their" Chris Rennard. For while Rennard enjoys a rather lower profile than New Labour's sultan of spin, the Liberal Democrats' own election guru is a no less formidable operator. True, Rennard has not managed to take the Liberal Democrats to Downing Street with a landslide majority, but it is in large part to him that the party owes its revival, the latest evidence of which was its victory in Brent East." As Chief Executive, Rennard oversaw the party’s recovery from a series of crises in January 2006 when Charles Kennedy resigned as Leader, Mark Oaten resigned as the party’s Home Affairs spokesman and Simon Hughes was claimed to be gay by "The Sun" newspaper. This turbulent period came to an end in March when he oversaw victory in the 2006 Dunfermline and West Fife by-election, which brought the total of Liberal Democrats MPs to 63. He chaired the Liberal Democrat general election campaign for both Sir Menzies Campbell and Nick Clegg between summer 2006 and May 2009, when he stood down as Chief Executive of the Party.