Maricopa County, Arizona, Sheriff Joe Arpaio and Republican front-runner Donald Trump went back to basics Wednesday during the businessman’s first campaign rally following the fifth GOP debate in Las Vegas. While introducing the billionaire candidate, Arpaio reminisced about their friendship and their shared suspicion that President Barack Obama may have been born in Kenya.

“If you recall, five months ago, I introduced Donald Trump. At that time, I said a few things, we have something in common — the birth certificate investigation, which is still going on,” Arpaio told the crowd in Mesa, Arizona, a suburb of Phoenix. Trump stirred controversy in 2011 by saying he thought the president was lying about his birthplace. The White House, as Trump and others kept pushing the claim, eventually released copies of Obama’s long-form birth certificate on April 27 of that year. The documents showed that the president was born in Honolulu, Hawaii.

Trump now ducks questions about the controversy he helped fuel. Questioned after the Republican debate Tuesday night by MSNBC’s Chris Matthews, Trump looked to avoid the birther conversation.

“Is Donald Trump honest when he says that Barack Obama isn’t a legitimate president?” Matthews asked.

“I don’t talk about that anymore,” Trump replied. If he does, he offered, that issue becomes “all people talk about.”

Trump recently rose to his highest level of support yet in the Republican presidential race, according to an average of polls by Real Clear Politics. He is beating second-place Sen. Ted Cruz of Texas by 16.9 points in national polls with 33 percent of the vote. In some polls, he has reached 41 percent support in the large field. Behind Cruz, who sits at 16.1 percent, is Florida Sen. Marco Rubio, with 12.6 percent and then retired neurosurgeon Ben Carson, with 12 percent of national support.