(Reuters) - The race to win the Republican Party's presidential nomination to challenge President Barack Obama turns to states like North Dakota on "Super Tuesday" when 10 states hold primaries and caucuses.

Here are some facts about North Dakota's Republican caucuses.

* The caucuses are held in dozens of locations statewide and are open to anyone who can prove North Dakota residency. Voters must be affiliated with the Republican Party or intend to vote for the party in the general election, but the state Republican Party has no real way of binding voters to that promise.

* In 2008, former Massachusetts Governor Mitt Romney won the North Dakota caucuses with about 36 percent of the vote. Romney, former U.S. Senator Rick Santorum of Pennsylvania and Texas Representative Ron Paul have all campaigned in the state in recent days.

* North Dakota sends 28 delegates to the Republican National Convention in August. Delegates will be doled out proportionally, according to how much support candidates get.

* North Dakota emerged mostly unscathed from the recent U.S. recession. It has one of the country's lowest rates of foreclosures and credit card defaults and the unemployment rate was only 3.3 percent in December of 2011, according to the U.S. Bureau of Labor Statistics. The state's economy is powered by the agricultural and energy industries, and has been rated one of the top states for start-ups.

* North Dakota has been a safe state for the Republican Party, which has won the state's vote in each of the last 10 presidential elections.

(Reporting By Lily Kuo; Editing by Deborah Charles and Eric Beech)