There is unlikely to be much suspense or spontaneity at the conventions of the Democratic and Republican parties -- held in the East Coast cities of Boston and New York, respectively. The two candidates are already known, and the major party positions will be agreed ahead of time.
But the meetings provide an opportunity for candidates and their parties to capture the attention of undecided or indifferent voters. In a year like this, in which nearly 20 U.S. states are said to be electoral battlegrounds, the conventions are a crucial chance for party workers throughout the country to shape their message and strategize.
Rob Ritchie is director of the Center for Voting and Democracy, an independent organization devoted to election reform. He tells RFE/RL that conventions help define a party:
"Even with all these things one can do by e-mail and fax and letter, there is something [valuable] that comes from getting together and meeting and talking as a national party -- rather than as a collection of state parties -- that a convention uniquely does. That's not necessarily something in the public eye, but it's a very important part of a party's long-term trajectory."
Conventions are also a useful gauge of party enthusiasm, says Jim Gerstein, director of Democracy Corps, a political research organization supportive of the Democratic Party. Gerstein says he expects there to be rousing support for presumptive Democratic Party nominee John Kerry, based on polling data and Kerry's successful fund-raising:
"There is an enormous amount of energy out there, and I think that will be something to observe and witness at the convention. And I think you also will have various themes throughout the convention that demonstrate the direction the party is taking."
But other analysts note that political marketing is now so sophisticated that most television viewers will see only what the campaign wants them to see.
Patrick Basham of the Cato Institute, an independent policy institute in Washington, tells RFE/RL that conventions have turned into massive public relations campaigns for the party's nominee: "Those running the convention, which basically means the Kerry campaign, they will do every thing they can to choreograph what the public sees and the media hears to ensure that a united front is presented. So while there will always be disputes and dissension from certain parts of the party, for whatever reason, they are going to keep those as far away from the podium and as far away from the lights and the cameras as possible."
This year's conventions will barely resemble the events held every four years from 1832 until the middle of the 20th century. For much of U.S. history, conventions were scenes of great drama, where party delegates held votes for a presidential and vice presidential nominee and established a party platform, or statement of principles.
At the 1912 Republican convention, a dispute between former President Theodore Roosevelt and William Howard Taft resulted in Roosevelt supporters withdrawing from the convention and forming the Progressive Party. In the subsequent three-way contest, Democrat Woodrow Wilson was elected chief executive.
In 1924, the Democrats cast 103 ballots before nominating John Davis, who was defeated by Republican Calvin Coolidge.
But after World War Two, direct primaries began to play a larger role. Under this system, party members were able to vote for delegates pledged to particular candidates, taking away the convention's role in selecting the party's chief candidate. Since 1952, only single ballots have been needed to select nominees.
Basham of the Cato Institute: "The convention was everything. That's evolved somewhat as the political system has become more bottom up, more grassroots. The decision is now made in the primaries and caucuses, but it isn't ratified until the convention. So, John Kerry, for example, isn't yet the candidate, although we all know he is going to be. He is not the official candidate until the convention in Boston."
The first two days of the Democratic convention (Monday and Tuesday) will be devoted to speeches by prominent party members, rallying the crowd and criticizing the opposing party.
Day three on Wednesday will see the ratification of John Edwards, the nominee for vice president.
On the fourth and final day, Thursday, the ratification of John Kerry as the presidential candidate will take place, followed by the climax of the convention -- Kerry's acceptance speech.