Democratic Sen. Barack Obama has begun airing a Spanish-language ad on radio stations in Nevada, introducing himself as a "son of a foreign father," his presidential campaign said Tuesday.

The ad, the campaign's first media buy in the state, emphasizes Obama's religious affiliation, his call for unity and his father's immigrant background.

"As a son of a foreign father who came to this country looking for a better life, Barack Obama learned that differences do not divide, but rather enrich," the ad says. The Illinois senator's father was from Kenya.

Hispanics make up nearly a quarter of the population in Nevada and are expected to be a key voting bloc for Democrats competing in the state's Jan. 19 caucus, the second in the nation.

Obama campaign manager David Plouffe said he expects Hispanics
to make up 6 percent to 10 percent of Democratic caucusgoers. He
said the campaign's ad plays to Hispanics' increasing disillusionment with Washington politics.

"What we see is the country as a whole is very frustrated with the way Washington works, or doesn't work," he said. "In the Hispanic community I think there's an even more intense feeling that Washington doesn't listen, doesn't hear."

The 60-second ad, which began airing Tuesday morning, also emphasize the senator's family and religious background.

"If you still want to know more, let us tell you Barack Obama is a Christian man committed to our community, his wife and his daughters," it says in Spanish.

The ad is running on stations in Las Vegas and Reno. The campaign would not release the size of the ad buy.

In July, New Mexico Gov. Bill Richardson was the first Democrat in the field to launch radio ads, both in English and Spanish, in Nevada.

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