9 March 2008 returns from an offiical source: Primarias 2008

There are two major parties in Puerto Rico:

• The Popular Democrats (in Spanish: Partido Popular Democrático, usually abbreviated as PPD) have tended to be pro-Commonwealth and, hence, largely anti-Statehood (though there has been a minority pro-Statehood faction within the PPD) and tends to be more or less aligned with the Democrats of the US.
• The New Progressives (in Spanish: Partido Nuevo Progresista and abbreviated PNP) tend to be somehat more pro-Statehood than the PPD and also tend to be the more aligned with the Republicans in the US.

[There is also the minority Puerto Rican Independence Party (in Spanish: Partido Independentista Puertoriqueño- or PIP) as PR's principal "third Party"] .

However, any apparent connection of the two major Puerto Rico parties to the two US Major Parties (outside of the selection of Puerto Rico's delegates to each Party's National Convention) is as much one of convenience as it is of reality (the PPD tends to be the more liberal Party [and, much like the Democrats in the US, it is a coalition of political factions ranging from the moderately conservative to the somewhat radically socialist], while the PNP tends to be the more conservative Party [and, much like the GOP here, is the more homogeneous of the two-- with fewer "wings", most to the right of center]). Therefore, when relating the two major Parties in Puerto Rico to the two Major US Parties, one must do so most carefully, as such connections are, in the main, still rather indirect.

There are separate Democratic and Republican Party organizations (not directly connected to the Party organizations of the PPD or PNP) in relation to the Commonwealth's selection of delegates to the Major Parties' respective quadrennial National Conventions.