Harry Hamburg, File, Associated Press
FILE - In this March 15, 2011 file photo, Rep. Dean Heller, R-Nev. is seen in his office on Capitol Hill in Washington. Nevada Gov. Brian Sandoval has named Heller to replace John Ensign in the U.S. Senate.

CARSON CITY, Nev. — Nevada Republican U.S. Rep. Dean Heller will replace John Ensign in the U.S. Senate, Nevada Gov. Brian Sandoval announced Wednesday.

The appointment was anticipated and sets up a political scramble on how Heller's House seat will be filled. State law says a special election must be held within 180 days of a vacancy.

Ensign has been dogged by an ethics investigation and announced last week he was resigning effective May 3.

Heller last month said he would run for Ensign's seat in 2012, and Sandoval quickly endorsed him.

In a statement, Sandoval said Heller "is an experienced representative who is ready for the responsibilities of this office, and who will work hard, not just for Nevada, but for the entire nation."

"A fiscal conservative who believes in limited government, Dean will fight to keep taxes low and balance the federal budget," Sandoval said. "He understands that the federal government spends too much money and places too many regulatory burdens on small business."

Sandoval said he was working with the secretary of state's office to determine how a special election would be conducted. Nevada has never had to fill a House vacancy, and state laws are vague.

Once a House vacancy occurs, the governor has seven days to set the date for a special election, which must be held within six months.

But there are questions over whether candidates would be chosen by political party central committees, or if it would be open to anyone interested in running.