But the contest - an opening round, but no less crucial for that - was Clarke v Cameron. They did not disappoint. It is a pity that the party's leadership rules do not permit more than two candidates going forward to be voted on in the constituencies. Unless the MPs' favourite, David Davis, somehow exits early, however, it is likely to be either Mr Clarke (who is a director of this newspaper) or Mr Cameron, who presents the alternative to Mr Davis, but not both. Depending on the mood of MPs, it could even be neither.
Which would be a shame. It could also spell the ultimate decline of the Tory party as a political force. As yesterday's duel showed, however, there is life in the old party yet, and Clarke v Cameron showed just how effective an alert party leader, plugged in to the realities of life in today's Britain, could be. The two were well matched. Each in his own way exuded both competence and confidence; their agendas were not a million miles apart. And it was not David Cameron's fault that the distinction between men and boys came to mind well before Kenneth Clarke reached his rousing finale.
Mr Cameron advertised his relative youth and his potential to impressive effect. He covered the waterfront, springing elegantly from the broad principles of high politics to the nuts and bolts of social policy, and back through the further reaches of abroad. His point that a Conservative foreign policy under Cameron would not stop at Zimbabwe and Gibraltar, but would embrace Darfur and the rest of Africa, was well made; his positive tone throughout was refreshing.
If David Cameron represents one - eminently plausible - face of the Conservative Party's future, however, Kenneth Clarke surely established that it was too early, far too early, for the party to consign him to its past. In terms of energy and vigour, it was hard to believe that, at 65, he is almost twice as old as Mr Cameron. In terms of authority and gravitas, on the other hand, the weight of those additional years placed him in quite a different league.
In what amounted to a superior job application, Mr Clarke set himself three tasks. First, to demonstrate that his ambition was undiminished, despite his age and despite his rejection by the party in the past. Second, to establish that his qualifications made him as worthy of election as Gordon Brown, both as party leader and prime minister. Third, to show how he would acquit himself against Tony Blair. He convinced on all three counts, but especially on the last.
By singling out "spin" and Mr Blair's style of government, Mr Clarke demonstrated both his old-style Tory credentials as defender of the unwritten constitution and an acute awareness of what concerns so many voters about Mr Blair. Always bluff, he was in character when he promised, if elected, to "say what I think and do what I say" and deliver "politics unspun".
At the very least, Mr Clarke made us wistful for the confrontations that might have been across the dispatch box, had Mr Clarke led the Conservatives over these past four years. At most, he has won the chance to show - at the third time of trying - how a credible Opposition would cope with Mr Blair and New Labour.