WASHINGTON  With Republicans hoping to recapture a number of statehouses in November, the media conglomerate headed by Rupert Murdoch is inserting itself into the races in bold fashion with a $1 million donation to the Republican Governors Association.

The contribution from Mr. Murdoch’s News Corporation, which owns Fox News, The Wall Street Journal, The New York Post and other news outlets, is one of the biggest ever given by a media organization, campaign finance experts said.

Democrats seized on the donation as evidence of the News Corporation’s conservative leanings, with Media Matters for America, a liberal group that has tangled often with the company, calling it “an appendage of the Republican Party.”

But News Corporation executives said the political priorities at the Republican Governors Association and its emphasis on low taxes and economic growth dovetailed with the company’s own concerns. “News Corp. has always believed in the power of free markets, and organizations like the R.G.A., which have a pro-business agenda, support our priorities at this most critical time for our economy,” said Jack Horner, a company spokesman.