With that in mind, campaign and party lawyers are dusting off their party rule books, running through decades-old procedural arcana and studying the most recent convention-floor fight, between Ronald Reagan and President Gerald R. Ford in 1976. Republican officials also are bracing for the possibility of a prenomination clash between the party’s establishment and members of the Tea Party movement, many of whom may be attending their first national convention…

Yet Mr. Santorum has hired a delegate specialist to comb through the patchwork of state-by-state rules and to find unpledged delegates who could swing to him in a floor fight, an effort Mr. Romney’s campaign says it is prepared to counter. Newt Gingrich’s team is expected to hold on to its delegates even if it is clear that he has fallen short — if only to keep Mr. Romney from reaching a majority.

And the Republican National Committee has alerted the Committee on Contests to be ready for action, preparing for the possibility of courtroomlike hearings run by lawyers that could decide whether the nomination is settled before party members take their seats in the Tampa Bay Times Forum sports arena…

“Roughly translated, that means, ‘We’re planning on ensuring the party can’t choose a nominee until September, with 60 days to take on an incumbent president who will have $1 billion,’ ” Ms. Chen said, referring to an often disputed estimate of Mr. Obama’s fund-raising goal.