That work, he added, won't be easy or fun, but it's essential.
"If conservatives do not do this work, we will lose in 2014, and 2016, and beyond," he said. "We will lose, and we will deserve to lose."
Many in the crowd, which had just heard from Sen. Marco Rubio, R-Fla., left the hall as Lee came to speak, but those who remained cheered on the Utahn.
The theme of Lee's speech mirrored that of other conservative luminaries who told the packed Gaylord National Resort convention hall that it's their job to use the momentum that launched the tea party onto the national stage and their candidates for Congress to keep the movement going by rallying around ideas and not just homemade signs.
"We've got to start talking about what we're for and not what we're against," said New Jersey Gov. Chris Christie. That's because of "one simple reason: Our ideas are better than their ideas, and that's what we have to stand up for."
Rep. Paul Ryan, a Wisconsin Republican who was his party's 2012 vice presidential nominee, noted that he had only eight co-sponsors on his budget proposal when he first introduced it but now the GOP-led House has passed it three times.
"That's how it always is: You fight it out. You figure out what works. You come together. Then you win," Ryan said. " It's messy and noisy and even a little bit uncomfortable. But the center of gravity is shifting. We're not just opposing a president. We're developing an agenda a modern, pro-growth, principled agenda for our party."
Ryan's budget, of course, has not passed the Democrat-controlled Senate.
Democrats on Thursday spent time zipping fact checks on the conservative speakers and responded to the event's theme as a tried-and-failed strategy.
"During the 2012 election, Republicans opposed comprehensive immigration reform with a path to citizenship," said Pili Tobar, western regional press secretary for the Democratic National Committee. "Today they are blocking reform from moving forward in the House of Representatives. In 2011, they jeopardized the nation's credit rating for their own political gain and they did the same last year."
"Republicans' policies and tactics aren't new; they're the same out-of-touch policies they've championed for years. Whether they're blocking legislation or proactively supporting their extreme policies, one thing is true: Republicans are on the wrong side of everyday Americans," said Tobar.