A congressional candidate who cast doubts about President Obama's birth certificate has lost the support of the major newspaper in his district.

The Charlotte Observer has rescinded its endorsement of Republican Jim Pendergraph, a leading candidate seeking to replace retiring Rep. Sue Myrick , R-N.C.

Pendergraph, a former Mecklenburg County sheriff, fell out of favor with the newspaper when he sided with Arizona Sheriff Joe Arpaio, who has investigated the authenticity of Obama's birth certificate.

"I have reason to be suspicious," Pendergraph told the Charlotte newspaper, a few days after he was endorsed by Arpaio. "But I don't know. I haven't seen the facts. I think there's a lot of smoke and generally when there's smoke there's got to be fire somewhere."

Obama was born in Hawaii, but the issue of whether his birth certificate is valid -- and his presidency is legitimate -- still continues to be an issue for some people. Obama's re-election campaign recently poked fun at Arpaio, as he held a news conference saying the president's birth certificate is a fake.

Richard Hudson, another GOP congressional candidate in North Carolina, reportedly told a campaign audience that "there's no question President Obama is hiding something on his citizenship," according to Roll Call.

North Carolina is a key battleground state in the presidential election, and one where Obama would like to repeat his 2008 victory. The state also has a couple of high-profile races that could help determine which party controls the U.S. House.