Rand Paul on Rachel Maddow show

WASHINGTON — Rand Paul, the Tea Party candidate who challenged the Republican establishment to win the party’s Senate nomination in Kentucky two days ago, criticized a landmark civil rights law on Thursday, landing himself in a potentially damaging dispute over civil rights and race.

In doing so, he provided Democrats an opportunity to portray him as extreme and renewed concern among Republicans that his views made him vulnerable in a general election.

Mr. Paul, in a series of television and radio interviews, suggested that the Civil Rights Act of 1964 was too broad and should not apply to private businesses, such as luncheonettes. As his statements drew a swarm of attacks from his opponents, Mr. Paul issued a statement declaring that he would not support repealing the landmark 1964 statute and blaming political opponents for trying to distort his views by saying he favored repeal.

“Let me be clear: I support the Civil Rights Act because I overwhelmingly agree with the intent of the legislation, which was to stop discrimination in the public sphere and halt the abhorrent practice of segregation and Jim Crow laws,” he said. Later, in an interview on CNN, he said that if he had been in the Senate in 1964, he would have supported the act.

Still, it was not clear that he had quelled rising concerns among Republicans about his ability to win in the general election, especially given his libertarian views in favor of limiting the role of government. “I hope he can separate the theoretical and the interesting and the hypothetical questions that college students debate until 2 a.m. from the actual votes we have to cast based on real legislation here,” said Senator Jon Kyl of Arizona, the Senate’s No. 2 Republican.

Democrats quickly mobilized to draw attention to what they cast as out-of-the-mainstream positions espoused by Mr. Paul — from raising the Social Security retirement age to 70 to questioning the legality of the Americans with Disabilities Act — as they sought to discredit what Jack Conway, the Democratic Senate candidate in Kentucky, described in an interview as Mr. Paul’s “narrow and rigid philosophy.”

The Tea Party phenomenon has provided a bolt of energy for the Republican Party. But the case of Mr. Paul also shows the risks that have emerged as new figures move to the forefront of conservative politics, as candidates with little experience and sometimes unorthodox policy positions face the kind of scrutiny and pressure that could trip up even the most experienced politicians.

Mr. Paul said in an interview with Rachel Maddow on MSNBC on Wednesday night that he supported the sections of the Civil Rights Act that applied to public accommodations but had concerns when it came to its applicability to private business; he raised similar concerns earlier in the day about the Americans with Disabilities Act in an interview on National Public Radio.

Asked by Ms. Maddow if a private business had the right to refuse to serve black people, Mr. Paul replied, “Yes.”

“I’m not in favor of any discrimination of any form,” Mr. Paul continued. “I would never belong to any club that excluded anybody for race. We still do have private clubs in America that can discriminate based on race. But I think what’s important about this debate is not written into any specific ‘gotcha’ on this, but asking the question: what about freedom of speech? Should we limit speech from people we find abhorrent? Should we limit racists from speaking?”

“I don’t want to be associated with those people,” he said, “but I also don’t want to limit their speech in any way in the sense that we tolerate boorish and uncivilized behavior because that’s one of the things freedom requires is that we allow people to be boorish and uncivilized, but that doesn’t mean we approve of it.”

While those views reflect the libertarian philosophy that Mr. Paul and many Tea Party members have embraced, they are politically treacherous for someone making an appeal to the electorate at large, as Mr. Paul learned as he struggled with questions about whether he thought the government had a role in regulating food safety and working conditions.

Congressional Republicans were peppered with questions about Mr. Paul’s position on civil rights. “I just want to be on the record that I believe the Interstate Commerce Clause was properly used by the courts and the Congress to make sure that when you travel in this country you can’t be denied food and lodging based on your race,” Senator Lindsey Graham, Republican of South Carolina, said. “That is not a big heavy lift for me.”

Mr. Paul’s father, Representative Ron Paul, a Texas Republican who ran for president in 2008, angrily defended his son, saying he was being treated unfairly. “I think there’s a lot of resentment because he became a star,” said Mr. Paul, who ran for president in 2008.

Democratic leaders have long said that they viewed Mr. Paul as the weaker of the two major candidates in the Republican primary — the other was Trey Grayson, the secretary of state — because, they said, his views would not be embraced by the general electorate as they were by primary voters. That view was shared by many establishment Republicans, as reflected by the fact that Senator Mitch McConnell of Kentucky, the minority leader, did not support him in the primary.

Mr. Paul also found himself on the defensive on Thursday when he sought to justify his decision to hold his election night celebration at a country club in Bowling Green, arguing that was not in any way at variance with the grass-roots movement he has come to epitomize.

“I think at one time, people used to think of golf and golf clubs and golf courses as being exclusive,” Mr. Paul said in an interview with ABC’s “Good Morning America,” adding, “Tiger Woods has helped to broaden that, in the sense that he’s brought golf to a lot of the cities and to city youth.”

Representative James E. Clyburn, the Democratic majority whip, who was active in the civil rights movement during the 1960s, described Mr. Paul as “extreme” in an interview. Mr. Clyburn said Mr. Paul’s decision to hold his victory rally at a country club was a slap at his own supporters. “Who would have a victory party in a place where the minions who just voted for you ain’t welcome?” he said.

More broadly, Mr. Clyburn said that he viewed Mr. Paul, should he get elected, as a threat to gains made by the civil rights movement over the past 50 years, given his views on the Civil Rights Act. “If we see someone like this get elected to the United States Senate, that will be the first step in my opinion to turning back the gains that we started making way back in the 1860s,” he said.

Representative Al Green, a Texas Democrat, demanded on the House floor on Thursday afternoon that Mr. Paul explain his views, which Mr. Green said were painful to those who experienced segregation. Mr. McConnell said through a spokesman that he was a fervent backer of the civil rights law and welcomed Mr. Paul’s statement that he would not seek to repeal it.