Larry Kudlow
Sizing up last week's unexpected congressional win by Florida Republican David Jolly, Kim Strassel of the Wall Street Journal wrote, "The Republicans who win this fall will be those who have serious answers to the attacks leveled on them -- about Obamacare, the economy, women's and seniors' issues." Sound advice.

A few weeks earlier, pollsters John and Jim McLaughlin argued that to win big in November, the GOP cannot rely on Obamacare alone, unpopular as it is. More sound advice.

In particular, there must be a growth platform, aimed especially at the middle class, which continues to suffer in the fifth year of the so-called recovery with real median income dropping by 4 percent and broad-based unemployment measured at roughly 12.5 percent. Believe it or not, a new Wall Street Journal poll shows that a large majority of Americans still think we're in a recession.

So the challenge for the GOP is to drill home the old Ronald Reagan point that Republicans can increase take-home pay or after-tax income. That doesn't mean forgetting the Obamacare disaster, which, as many predicted, is falling of its own weight. The individual mandate is now dead. But it does mean the GOP must emphasize economic growth.

Fortunately, many of the party's top thinkers are already hammering away on the growth theme.

In Joint Economic Committee hearings this past week, Republican chairman Kevin Brady talked about the "growth gap," which describes the difference between the Obama recovery and other average recoveries of the past 50 years. America is missing 5.6 million private-sector jobs, reported Brady, and $1.3 trillion in real GDP from the economy.

Delivering the Republican party's weekly radio remarks last week, Sen. Rob Portman of Ohio reminded us that 11 million Americans have become so discouraged they've given up looking for work altogether, and that while poverty rates have gone up, the average family is now bringing home $4,000 less than they did just five years ago.

And in an interview with Sen. Marco Rubio this past week, I heard a number of strong growth ideas. For instance, building a national infrastructure network of interstate pipelines -- like Keystone -- to expedite the boom in oil and natural-gas shale development. This building can include rapid permitting for liquid natural gas projects. As Rep. Paul Ryan noted in another interview, the energy play for making and exporting LNG would remove Vladimir Putin's energy death grip on Ukraine and the rest of Europe.

Larry Kudlow

Lawrence Kudlow is host of CNBC’s “The Kudlow Report,” which airs nightly from 7 p.m. to 8 p.m.