Sen. Rand Paul, the maverick first-term senator who rode a tea party wave from a Kentucky ophthalmology practice to Congress, made a vigorous appeal Tuesday to conservatives angry with both parties as he entered the race for the Republican presidential nomination.

Unveiling his campaign at a hotel ballroom here, Paul offered himself as a singular voice and fresh-faced disrupter of the entrenched political order.

Paul’s appeal was rooted in part in the purist libertarian plank championed for decades by his father, former Republican presidential candidate Ron Paul. But the senator also seeks to move beyond his father’s base by stitching together a nontraditional coalition among disparate blocs of voters who share frustration with the federal government’s role in their lives, whether evangelicals, tea party activists or tech-savvy millennials.

Paul pledged to be a combative envoy in a crowded and competitive GOP field that is likely to feature at least a half-dozen formidable candidates.

Sen. Rand Paul (R-Ky.) officially announced his campaign for president in 2016 in his home state of Kentucky. Here are his full remarks. (AP)

“I have a message, a message that is loud and clear and does not mince words: We have come to take our country back,” Paul said at the start of a 30-minute speech heavy on populism. “We have come to take our country back from the special interests that use Washington as their personal piggy bank.”

Flanked by American flags, Paul, 52, emphasized inclusion for a party that has struggled to adapt to national demographic changes and has fumbled the past two presidential elections. While the setting was one of a classic launch — a dark-suited, flag-pin-wearing senator speaking on a ballroom stage — Paul said he would reach out to all Americans who have tuned out of the political process and have become weary of partisanship.

Paul fleshed out pillars of his emerging, eclectic platform: amending the Constitution to require a balanced federal budget and congressional term limits, offering “school choice” for students, making investments in the nation’s highways and bridges, and repealing “any law that disproportionately incarcerates people of color.”

“The message of liberty, opportunity and justice is for all Americans, whether you wear a suit, a uniform or overalls, whether you’re white or black, rich or poor,” Paul said. “Many Americans, though, are being left behind. The reward of work seems beyond their grasp. Under the watch of both parties, the poor seem to get poorer and the rich get richer.”

His pitch illustrated the promise and peril of Paul’s unorthodox campaign, which calls for lifting the poor out of poverty and getting them back to work while also demanding a drastically reduced role for government. This tension was on display in the wordy campaign slogan attached to his lectern: “Defeat the Washington machine — Unleash the American dream.”

But this amalgam of ideas also makes Paul a potent threat to the rest of the GOP field. Paul comes from the dovish wing of the Republican Party and is reluctant to meddle in foreign affairs unnecessarily. He bashes Republicans and Democrats with impunity, telling the crowd here that he blames both sides and the political system for the loss of opportunity. And he rails against corporate influence in a party that is dominated by business.

Paul’s likely rivals are carving out their own primary profiles. Several conservative contenders are actively working to prevent Paul from sewing together the coalition he seeks, in particular Paul’s friend in the Senate, Ted Cruz of Texas.

Sen. Rand Paul, (R-Ky.), who announced he's running for president in 2016, is known for his belief in limited government. Here his take on the Affordable Care Act, the Constitution and more, in his own words. (Julie Percha/The Washington Post)

Cruz, who announced his campaign last month in front of thousands of young Christians at Liberty University in Lynchburg, Va., has also sought to portray himself as a Washington outsider and has made overtures to both libertarians and evangelicals.

Competing with Paul for the votes and donations of anti-tax, business-minded Republicans are former Florida governor Jeb Bush, Wisconsin Gov. Scott Walker and Sen. Marco Rubio of Florida. Retired neurosurgeon Ben Carson, former senator Rick Santorum of Pennsylvania and former Arkansas governor Mike Huckabee are all vying for the religious right.

Paul has reserved some of his toughest barbs and public attacks for the likely Democratic front-runner, Hillary Rodham Clinton, who is expected to announce her candidacy this month. ​

Defense hawks have reacted with particular alarm at the idea of Paul as the GOP nominee. A conservative advocacy group, the Foundation for a Secure and Prosperous America, released a television spot to air in early primary states this week that casts Paul as “dangerous” on international affairs and aligned with Obama on nuclear negotiations with Iran.

“His problem is that his ambitions are in conflict with his actual principles,” said John R. Bolton, a U.S. ambassador to the United Nations in the George W. Bush administration who is mulling his own 2016 presidential bid. “Many people who like Rand Paul on fiscal and economic issues are appalled by his views on national security and his lack of understanding.”

In his remarks, Paul said he was not an isolationist but a non-
interventionist — supportive of the U.S. military forces but cautious about deploying them beyond a response to direct threats. He said his worldview was more akin to Ronald Reagan’s than George W. Bush’s, while also declaring that “the enemy is radical Islam” in current global conflicts.

“Conservatives should not succumb . . . to the notion that a government inept at home will somehow succeed in building nations abroad,” Paul said. “I envision a national defense that promotes, as Reagan put it, peace through strength.”

Paul also offered a vivid critique of the National Security Agency’s surveillance policies during the Bush and Obama administrations. Holding up his smartphone and raising his voice, Paul decried “this vast dragnet by executive order.” As president, he said, “I will immediately end this unconstitutional surveillance,” drawing an enthusiastic response.

Paul’s prepared text and delivery was unusually disciplined for a politician who prefers to speak extemporaneously and fills his occasionally rambling speeches with little-known historical asides and riffs on monetary policy. While he shouted at points Tuesday and become passionate during a passage on the sweeping powers of the NSA, he largely kept his remarks upbeat and connected to his core outsider theme.

Paul heads to New Hampshire on Wednesday and will address what he calls the “leave me alone” coalition in the flinty, libertarian-leaning state. Then he pivots Thursday to military-heavy South Carolina, where he is expected to talk about defense in front of an aircraft carrier.

Notably lacking from Paul’s speech was a forceful embrace of the libertarian ideology that his family has made its signature. Paul nodded to his political roots and applauded for his father, who sat in the audience, but he repeatedly portrayed himself as a contender for the nomination rather than a fringe candidate looking to make a point.

Paul instead returned to the tea party ethos that elevated him during his 2010 Senate race, in which he came from behind in the polls to beat the GOP establishment’s handpicked candidate. He spoke again to those conservative voters who had become fed up with the Republican Party of the George W. Bush era, chastising the last “Republican administration” that oversaw an increased federal deficit and channeling their resentment with other White House hopefuls as a continuation of the status quo.

Paul’s launch also gave voters a softly lit introduction to his upbringing and his decision to pursue a career in medicine, which he credited to watching his grandmother suffer vision problems. Paul, whose biography is so frequently intertwined with his father’s, used the moment as a chance to cite other inspirations. In contrast to her taciturn spouse, Kelley Paul gushed about her “awesome” husband: “You are brave. You inspire others.”

Rand Paul’s campaign strategy has been in the works for years. Crafted by his chief political adviser, Doug Stafford, it centers on positioning Paul for what could be a drawn-out fight for the GOP nomination, lasting for dozens of primaries and perhaps until the Republican National Convention.

With survival the imperative, Paul is eagerly searching for wealthy financiers to supplement his grass-roots network, attending Mitt Romney’s donor summits in Utah and hosting his own conclaves. Expanding his organizing in caucus states, where Ron Paul did well in 2012, is another objective.

The packed crowd at the Galt House Hotel in downtown Louisville was a mix of longtime Paul supporters and conservatives inspired by the Obama-era tea party movement. Many were sporting Paul buttons and chanted “President Paul” at times during his speech.

“I would describe this country as a dump and Senator Paul is here to clean it up,” said Jennifer Wang, 35, of Louisville. She works at a grocery store and registered to vote for the first time to support Paul’s presidential bid.

Martina Kunnecke of Louisville, by contrast, described herself as “very left-wing” but said she likes what Paul has to say about helping poor urban neighborhoods. She isn’t sure she would vote for him, but she will be watching him closely.

“I’ll take a serious listen,” she said.

Costa reported from Washington.