The conventional wisdom about debates also sometimes evolves in a way that differs from the initial reaction to them.
Mr. Gingrich's other economic ideas, for example as seen in the latest debates, also seem to be edging toward the less serious side of Republican policy proposals — including very large tax cuts that would greatly increase the deficit.
For example, a Google search Friday on the TV debates also brought up a sponsored link to a Conservative Party Web site highlighting the most favorable opinion poll for Mr. Cameron.
Mr. Downey, who has been helping Mr. Gore prepare for the Bush debates and was standing in for Mr. Bush in mock debates, also said he would recuse himself from any further debate preparation.
Debates also represent one of the rare times when a candidate can speak directly to an enormous number of voters, without having to rely on the conduit of journalists, and for Mr. Bush, that is more attractive than ever before.
As well as the 30 April two-leader clash, the broadcasters have proposed seven-way debates also involving Mr Clegg and the leaders of Ukip, the Greens, Plaid Cymru and the Scottish National Party on ITV on April 2 and BBC on April 16.
