No sooner had John Boehner announced his decision to resign as speaker than conservatives were lamenting the heir apparent.

California Congressman Kevin McCarthy, who has a lifetime rating from the American Conservative Union of 89 percent, is under fire for not being conservative enough. The opportunistic Constitutional Rights PAC has even mounted a “Fire McCarthy” fundraising campaign.

These attacks on California’s favorite son are dead wrong. Speaker Kevin McCarthy will not only advance the conservative cause, he could be the most consequential speaker since Newt Gingrich inspired the country with his Contract with America.

I say this with confidence because I’ve made the same mistake of doubting McCarthy’s conservative credentials. When I served as chairman of the California Republican Party, I was one of many conservatives apprehensive of McCarthy’s election to the State Assembly.

In the 2002 primary, McCarthy was the lone moderate to survive a nasty round of “conservative vs. liberal Republican family fights.” He had a reputation from his Young Republican days of outmaneuvering conservatives in internal party battles, and even worse, was seen by many as on the fast track to leadership.

It took McCarthy less than a year to be unanimously elected Republican leader.

“Kevin McCarthy’s election as the new leader-to-be of the Republicans in the Assembly occurred so smoothly and quietly that many people didn’t notice how unusual it was,” Vic Pollard, a longtime political reporter for theBakersfield California wrote in November 2003. “He was elected unanimously, by all accounts, in a caucus so notoriously fractious that few leaders in recent years have been able to collect majorities of more than one or two votes.”

How’d McCarthy assuage conservatives’ fears?

He gave them control of caucus policy. McCarthy tapped future Congressman and then-Assemblyman John Campbell to serve as the GOP lead on budget issues. Conservative stalwart Ray Haynes was tapped as “the point man on policy debates for the caucus.” Conservative lawmakers Tony Strickland and Rick Keene were both given top leadership posts.

And McCarthy? He made it his mission to raise money for his caucus and elect more Republican members to the State Assembly. In the 2004 election cycle, McCarthy contributed more than $800,000 from his own campaign account to support his colleagues, a figure that doesn’t include hundreds of thousands of dollars raised through party committees. McCarthy’s fundraising and campaign operations expanded the field of play and put Democrats on the defensive in a high turnout presidential election year.

In 2004, California Journal gave McCarthy its “Rookie of the Year” honors over Democrat Assemblyman Fabian Nunez, who’d managed to become Speaker of the Assembly as a freshman. California political observers noted McCarthy’s “quick grasp of issues and politics” and ability to score “quick victories on ideological grounds.”

“McCarthy has been the better leader, noting that he had united and re-invigorated his caucus and had become, in a short time, the quickest study in the Assembly,” California Journal wrote in its annual awards issue.

During McCarthy’s tenure as Assembly Republican leader, he maintained a united caucus that refused to bend on tax increases. His unwillingness to compromise with legislative Democrats and ability to keep his troops in line “immensely strengthened the governor’s negotiating hand,” the conservative California Political Review observed.

In fact, McCarthy’s time in Sacramento working in the minority will make him a stronger speaker.

“When you’re in the minority, knowing the rules gives you greater strength,” he told California Journal. “One thing I’ve learned from the Democrats, having such a large majority, they don’t always learn all the rules because they don’t have to.”

Those years in the minority have already been put into practice. McCarthy proved his value by recruiting, advising many of the winners in the momentous House elections of 2010, the Tea Party Election. He will get elected Speaker primarily because of the many conservatives whose careers emerged because of McCarthy’s political strategic thinking.

If Republicans want to win the White House in 2016, it starts with electing McCarthy as Speaker in 2015.