UPDATE 1- Arizona appeals ruling on state's immigration law

(Adds Arizona governor comment, details)

PHOENIX, July 29 (Reuters) - Arizona lodged an appeal on Thursday seeking to lift a judge’s ruling blocking key parts of the state’s controversial law cracking down on illegal immigrants, the governor’s office said.

Lawyers for Governor Jan Brewer and Arizona asked the 9th U.S. Circuit Court of Appeals in San Francisco to lift a preliminary injunction blocking parts of the law, known as SB 1070, and sought to expedite consideration of the state’s appeal.

U.S. District Court judge Susan Bolton on Wednesday granted an injunction against the most controversial elements, which had drawn wide popular support in this state bordering Mexico.

“Today I filed an expedited appeal with the Ninth Circuit asking the court to lift the injunction put in place by Judge Bolton yesterday against certain provisions of SB 1070 and to allow those provisions to go into effect pending a decision on the merits of this case,” Brewer said in a statement.

“I have also asked the Ninth Circuit to expedite the briefing schedule and its ruling, since Congress and the President have once again failed to act,” she added.

The Republican-controlled state legislature passed the law three months ago to try to drive nearly half a million illegal immigrants out of Arizona, and stem the flow of human and drug smugglers over the border from Mexico.

Tensions over the law have inflamed a national debate over immigration, which has festered for decades and promises to play into the elections in November, when President Barack Obama’s Democrats are fighting to retain control of Congress.

There are an estimated 10.8 million illegal immigrants in the United States, a country of more than 300 million people.

Police arrested at least 30 protesters who took to the streets of Phoenix on Thursday to protest the law, even though its most intrusive provisions had already been blocked by a U.S. court