FACTBOX: Massachusetts and its February 5 primary

(Reuters) - Massachusetts is one of 24 U.S. states that holds its presidential nominating contest on February 5.

Following are a few facts about the Bay State and its primary:

* Republicans, including presidential candidate Mitt Romney, controlled the governor's mansion between 1991 and 2007. Otherwise, the Democratic Party has long dominated state politics. Both senators and all 10 members of the Massachusetts delegation in the House of Representatives are Democrats, and the governor's mansion and state legislature are currently in Democratic hands.

* This Democratic pedigree is reflected in the relative emphasis each party gives the state. Massachusetts will send 121 delegates to the Democratic convention but only 43 delegates to the Republican convention.

* Polls close at 8 p.m. EST. Both primaries are open to independent voters.

* Democratic candidate Barack Obama is backed by the state's three senior politicians: Gov. Deval Patrick; Sen. John Kerry, the party's 2004 presidential nominee; and Sen. Edward Kennedy. Nevertheless, a recent Rasmussen poll showed the Illinois senator trailing rival New York Sen. Hillary Clinton by 6 percentage points.

* On the Republican side, a recent SurveyUSA poll showed Romney leading rival Arizona Sen. John McCain by 21 percentage points.

* The state's professional sports teams have been remarkably successful in recent years. Baseball's Boston Red Sox won the World Series in 2004 and 2007, while the New England Patriots football team will try to cap a perfect season with a Super Bowl win on Sunday, in what would be their fourth championship since 2002. If they win, they would celebrate with a parade in downtown Boston on February 5.

(Reporting by Andy Sullivan; Editing by Bill Trott)

SOURCES: American Almanac of Politics, Real Clear Politics, U.S. Census Bureau

(For more about the U.S. political campaign, visit Reuters "Tales from the Trail: 2008" online at http:/blogs.reuters.com/trail08/)