The recent surprising news of the primary loss of Eric Cantor, the House Majority Leader, contains a mighty lesson for all incumbents, especially those in leadership: never forget the special interest group (voters) that sent you to Congress.

When I ran against the sitting Speaker of the US House in 1994 – and won – it was only the second time in US history (the first time since the Civil War) that such a victory had occurred. Generally, any loss by a House or Senate leader is rare. And, 95 percent of all incumbents are reelected. In my case, and in Eric Cantor’s case, the incumbent had a huge advantage – in campaign cash, in experience and in inside information that usually defeats challengers. The stars also need to align properly for a challenger to emerge victorious – then and now.

But oftentimes there’s also vulnerability – one that stems from the incumbent’s neglect of voters back home. Congressional leaders are beholden to many interest groups. That was the case generally in 1994 when Mr. Foley, as Speaker, seemed to pay more attention to his Washington, D.C. “constituents” – the president and his House colleagues – than the voters of eastern Washington. When a new person with a local set of qualifications came along as a challenger, the incumbent, even with oodles of campaign cash, had a fight on his hands. The most effective campaign slogan that year was, “We don’t need a Speaker, we need a listener.”

When Cantor used his substantial campaign cash against a long-shot challenger deemed to have little or no chance to win, and spent some of the last few primary days absent from his own District in Virginia, the dye was cast, just as in 1994. Voters were fed up and had the last word – no one is indispensable. Another slogan that tipped the balance in the challenger’s favor in Virginia’s 7th District might have been, “We don’t need a Majority Leader, we just need a leader.” Eric Cantor was a friend to many interest groups—Wall Street, the business community and both mainstream and conservative constituents. But his most important interest group was his 7th District voters.

Today, the Cantor outcome is a powerful lesson for all incumbents, but particularly those in leadership. Be able to answer the fundamental question, “How has your service in Congress helped the people back home?” Any incumbent who doesn’t have a ready and convincing answer had best beware because your time in Congress is likely short. A challenger will sneak up on you prepared to answer that question convincingly if given the opportunity. Professor Brat was able to assure voters who had previously been Cantor supporters that he had answers to America’s problems.

President Obama’s approval ratings hover in the low 40 percent range because he has largely fallen below the trust standard expected of all elected officials. Congress’ approval rating is even lower. Voters trust in elected officials to solve America’s problems. When they don’t, trust is broken and it’s hard to earn it back. Virginia voters lost trust in Eric Cantor, and Professor Brat was deemed a reasonable replacement.

Voters are now skeptical of all elected officials. Returning tax dollars to states and congressional districts no longer justifies reelection. Instead, voters expect national problems to be solved and political impasses to be overcome. They know the atmosphere in Washington is poisonous and they want it fixed. They realize every American owes some $53,000 on the national debt and they want that number reduced. They see political judgments dictating IRS policy and voters don’t like it. Voters see an unaccountable government, and they want it changed. Voters see more government dependency throughout our free enterprise system, and they object.

Radio talk show host Dennis Miller, commenting on the Cantor loss, ranted that Cantor should “get a job like the rest of us” and be dismissed from the ivory tower that has become the comfortable resting place of the national political class.

Twenty years ago, I made the point that for 30 years, my opponent had received a reliable government check, escaping the uncertainty that besets working class Americans trying to manage in the free market economy with its uncertainties of recessions, economic competition and private sector challenges. Incumbents today face the same anti-government objections because those operating our government have forgotten whose money pays their way.

The Cantor election outcome was less a shock and more a wakeup call for those entrusted to act responsibly for the people they represent.

George R. Nethercutt, Jr. served in the US House from 1995-2005. He is a lawyer and serves as chairman of the nonprofit George Nethercutt Foundation, dedicated to helping Americans, particularly students, receive a better civics education.