“This election will be about whose side you're on.”

The candidate saying that last week was New York City’s mayoral front-runner, Democrat Bill de Blasio, but it could have been nearly any Democratic politician. The de Blasio line reflects an important insight into politics: Many voters – especially those who are struggling – lean toward the candidate who appears to be on their side.

It's an insight the Right needs to absorb and make their own. Some conservative Republicans are beginning to get it.

“Today … we find the underprivileged trapped in poverty, sometimes for generations,” Sen. Mike Lee, R-Utah, said Tuesday. “We find the middle class caught on a treadmill, running harder every year. ...”

This may sound like basic common sense, but it’s not obvious to many Republicans.

Mitt Romney summed up his views on the working class in his famous 47 percent speech: People who don't make enough to owe income taxes (this could be a family of four earning $40,000) can't be convinced “that they should take personal responsibility and care for their lives.”

What effect did this mistaken view have on the presidential race?

Romney in 2012 won only 18 percent of voters who were looking primarily for a candidate who “cares about people like me.” Had Romney pulled in even 30 percent of this group, he would have won the popular vote.

Herman Cain was blunter: “If you don’t have a job and you’re not rich, blame yourself!”

The GOP isn’t monolithic on this point, though. In the Republican primaries, Rick Santorum presented a conservatism that didn’t equate material success with interior virtue, and he argued conservatives needed to gear their policies towards helping people who are struggling. These days, freshman Sen. Mike Lee is providing the contrast to Romney.

Lee, in his speech at the conservative American Enterprise Institute (where I am a visiting fellow), laid out a tax plan that smashes some GOP idols.

First, Lee’s plan isn’t a flat tax. He calls for a 15 percent rate and 35 percent rate. He puts much more emphasis on making the tax code clean and simple – eliminating deductions, streamlining returns – than on flatness. This tacitly accepts the notion of a progressive income tax code. He’s agreeing that the rich ought to pay a higher portion.

Along the same lines, Lee’s tax plan would cap the mortgage interest deduction at $300,000. Most homeowners would see no difference, but lobbyists living in Northwest Washington and Chevy Chase would see their deductions shrink.

Most importantly, Lee rejects the notion, persistent among some conservatives, that there’s something bad about knocking low-income families off the tax rolls. The centerpiece of Lee’s bill is an expanded child tax credit that would not only reduce income taxes to zero, but also offset payroll taxes.

In doing so, he explicitly rejects Romney 47-percentism: “Working families are not free riders.”

In short: Try to help the working class and the middle class by getting government out of their way.

But to prove to voters you are “on their side,” you also need to define “the other side,” and oppose it. For Lee, this means taking on crony capitalism.

“At the top of society,” Lee told the conservative crowd, “we find a political and economic elite that – having reached the highest rungs – has pulled up the ladder behind itself, denying others the chance even to climb.”

He continued in this libertarian populist strain: “From Wall Street to K Street to Pennsylvania Avenue, we find special interests increasingly exempted and insulated – by law - from the rigors of competition and from the consequences of their own mistakes.”

Lee said the U.S. economy is increasingly “rigged for big government, big business, and big special interests. And rigged against the ordinary citizens and forgotten families who work hard, play by the rules, and live within their means.”

Remember, this sort of talk isn’t coming from the squishy center, but from the Red Meat Right – from Utah, to be precise. And it could represent a much-needed libertarian-populist wave in the GOP because it comes from the same well from which the Tea Party sprung.

Lee came to Washington by beating the GOP establishment and K Street in his 2010 primary against “Bailout Bob” Bennett. Others who won in similar fashion – with the lobbyist and business PAC money aligned against them – include Senators Rand Paul, Ted Cruz, Marco Rubio, and Pat Toomey.

If Lee's ideas gain steam, we could see a Tea Party for the People.

Timothy P. Carney, The Washington Examiner's senior political columnist, can be contacted at tcarney@washingtonexaminer.com. His column appears Sunday and Wednesday on washingtonexaminer.com.