WASHINGTON (CNN) -- The GOP congressman from South Carolina who shouted out during President Obama's health care address to Congress insisted Thursday that his outburst was "spontaneous."
Rep. Joe Wilson shouts, "You lie!" after President Obama denies the health plan would cover illegal immigrants.
Rep. Joe Wilson shocked many observers Wednesday night when he shouted, "You lie!" after the president denied that health care legislation would provide free coverage for illegal immigrants.
Some people using Twitter suggested that Wilson's retort was planned and pointed to a comment the lawmaker posted on Labor Day:
"Happy Labor Day! Wonderful parade at Chapin, many people called out to oppose Obamacare which I assured them would be relayed tomorrow to DC," the tweet from Wilson's account said.
However, on the way to his office Thursday morning, Wilson said his outburst wasn't planned.
"It was spontaneous. It was when he stated, as he did, about not covering illegal aliens, when I knew we had those two amendments, and I say that respectfully," Wilson said.
He was referring to two amendments on one version of proposed health care legislation, which he said would have provided for verification of citizenship. Both of the amendments were defeated, he said. Fact check: Will plan cover illegal immigrants?
Wilson also cited a report by the Congressional Research Service that he said showed the health care proposals would include illegal aliens.
"And I think that is wrong," he said.
"We need to be discussing issues specifically to help the American people. And that would not include illegal aliens. These are people -- I'm for immigration -- legal immigration. I've been an immigration attorney. But people who have come to our country and violated laws, we should not be providing full health care services," he said.
A CNN review of the Congressional Research Service report found that the health care legislation does address illegal immigrants. It says that noncitizens who can be considered "resident aliens" under tax law, which doesn't distinguish between legal and illegal immigrants, would be required to buy health insurance.
Yet the proposal clearly says that federal subsidies would go only to U.S. citizens and immigrants who are in the United States legally.
Republican congressional leaders told Wilson on Wednesday night that they wanted him to tell the White House that his comments were "inappropriate," Wilson said Thursday. Watch the lawmaker describe his call to the White House »
Shortly after Obama's speech, Wilson called the White House and issued a statement apologizing for his "inappropriate and regrettable" comments.
According to Wilson, administration officials said they appreciated his call and emphasized the need for "a civil discussion."
"I certainly agree with that," Wilson said.
Obama told reporters at a Cabinet meeting Thursday morning that he accepted Wilson's apology. Watch the president say he appreciates the apology »
Democrats and Republicans have criticized the South Carolina congressman for what they described as disrespect for the president. Watch the outburst and the chamber's response »
Wilson's shout wasn't the only demonstration of displeasure that Republicans made during the speech.
Rep. Louie Gohmert, R-Texas, wore a sign around his neck that said, "What bill?" And when Obama asked Republicans to share their ideas to overhaul health care, a small group raised up a stack of papers above their heads. iReport.com: "You are disrespectful, sir"
After the speech, Sen. John McCain of Arizona, the Republican presidential candidate last year, called Wilson's outburst "totally disrespectful" and said he should apologize.
McCain told CNN's "Larry King Live" there was "no place for it in that setting or any other and he should apologize immediately."
Other Republicans also criticized Wilson, along with the expected Democratic condemnation.
"It was crude and disrespectful," said Senate Majority Whip Dick Durbin, D-Illinois. "I think the person who said it will pay a price."
House Majority Whip Jim Clyburn, D-South Carolina, said, "I was always taught that the first sign of a good education is good manners. I think that what we saw tonight was really bad manners.
"And having a spirited debate is one thing, exercising bad manners is another. That was beyond the pale -- and I would hope that he would publicly apologize on that same floor to the president of the United States for that insult."
And Wilson's outburst may come with a steep political price. iReport.com: Share your take on the speech
The five-term lawmaker represents the 2nd Congressional District, which includes the state capital, Columbia, and stretches to Beaufort and Hilton Head Island.
Wilson's likely 2010 Democratic challenger, Rob Miller, has raised more than $200,000 from 5,000 donors since Wednesday night, the Democratic Congressional Campaign Committee said.
Miller accused Wilson of "engaging in childish name-calling and disrespecting our commander in chief."
Wilson's shout prompted Democrats on the Internet to direct donors to Miller's Web site and to a Democratic fundraising site, ActBlue. iReport.com: Share your take on the speech
Miller gave Wilson the toughest re-election challenge of his career last year in one of the country's most conservative congressional districts. Miller lost by 8 percentage points. He plans to challenge Wilson again next year.
CNN's Peter Hamby and Deirdre Walsh contributed to this report.