Stunning upsets in a handful of primary races Tuesday made clear that the anti-incumbent, anti-establishment wave characterized by fiscally conservative "tea party" activists continues. What is less clear is whether those candidates can convince voters between now and the November elections what they stand for and how they would change government.

On the surface, the anti-incumbent mood of the country spells trouble for Democrats, because they control the House, Senate and the presidency. But below the surface, tea party activism has led to the defeat of establishment Republicans considered by many as best equipped to win in November.

So, the question remains: Will tea party enthusiasm burn out in the general election, allowing Republicans to snatch defeat from the jaws of victory?

Between now and the November elections, these political outsiders must prove they are competent and serious people with a sensible plan and workable objectives.

Even though it was controversial in some circles, the Republican revolution of 2004, led by former Speaker of the House Newt Gingrich, had the "Contract With America."

Republican challengers seeking to unseat incumbent Democrats in 2004 were able to offer voters a simple outline of a defined alternative, a different approach to government. Whether that plan was enacted or even pursued seriously is a matter for debate. But there was a clear plan — and voters responded.

Today's tea party candidates have, so far, offered no such plan. At this point, they represent anti-incumbent anger and a generally conservative approach to federal spending. Given today's lagging economy, high unemployment and the massive federal deficit, voter anger is easy to tap into. But general election voters, particularly independent-minded voters, will want more. They will want to know what they are voting for.

Some Republicans see the risks posed by this grass-roots, insurgent political movement.

David Frum, a former speech writer for President George W. Bush, said "Republicans have done insufficient serious policy work over the past half-dozen years. The legacy of this inactivity is a party on the brink of power, lacking the intellectual framework for the use of that power."

Tuesday's big wins for outsider, tea party-backed candidates have some Republican strategists worried about November. Karl Rove, the architect of Bush's election wins and a current party strategist, commented on Christine O'Donnell's upset win over a moderate, experienced, GOP-backed candidate in the Delaware Senate race, saying "This is not a race we are going to be able to win."

Just a few months ago, it looked like Republicans would cruise to easy wins in November, taking control of the House and Senate from Democrats. But recent primary wins by insurgents, generally backed by tea party groups in Florida, Colorado, Delaware, Nevada, Alaska, New York and elsewhere, are promising to turn this November's elections into interesting contests.

Being angry about the current state of affairs is understandable. But these insurgent candidates, generally not well-known, will have to offer a credible philosophy and a workable outline of principles or specific goals to attract enough voters to win in November.

If tea party-backed candidates can offer some clear, workable ideas, insurgents might succeed, because plenty of Democrats, as well as Republicans, are unhappy with the status quo.