(Xinhua)
Updated: 2008-01-17 10:46

WASHINGTON -- A total of six Democrats and seven Republicans will kick off the second bout of competition for their parties' 2008 presidential candidacy as New Hampshire primary is expected to start next Tuesday, which is a turning point for their path to the White House.

The following is a brief introduction about the presidential primary system of the United States:

As the first step in the process of the US presidential election, the primary is run by the state and local governments in the states which do not have caucuses instead.

Different from caucuses that gauge support for presidential candidates through local meetings of party members, primary elections gauge support through statewide direct voting.

The events determine which candidates will receive a state's votes for the Republican and Democratic nominations at the political parties' national conventions held later in the year.

Presidential primaries originated in the United States at the turn of the 20th century. The first presidential primary law was enacted in Florida in 1901, authorizing party officials the option of holding an election to choose national convention delegates.

The first preferential primary vote for president was held in 1910 in Oregon.

By 1912, a dozen US states have enacted presidential primary laws. The number has increased to 41 in 2000, while the rest are having caucuses.

Most states' primaries are binding, meaning that the results of the election legally bind some or all of the delegates to vote for a particular candidate at the parties' national convention, while a few states practice non-binding primaries, in which delegates are selected to a state convention and then decide their votes.

In the 2008 US presidential elections, apart from the states of Alaska, Colorado, Hawaii, Idaho (Democratic party), Iowa, Kansas, Maine, Minnesota, Nevada, New Mexico (Democratic party), North Dakota and Wyoming, the rest will run primaries.