The radical center is “radical” in its desire for a radical departure from politics as usual. It advocates: raising taxes to close our budgetary shortfalls, but doing so with a spirit of equity and social justice; guaranteeing that every American is covered by health insurance, but with market reforms to really bring down costs; legally expanding immigration to attract more job-creators to America’s shores; increasing corporate tax credits for research and lowering corporate taxes if companies will move more manufacturing jobs back onshore; investing more in our public schools, while insisting on rising national education standards and greater accountability for teachers, principals and parents; massively investing in clean energy, including nuclear, while allowing more offshore drilling in the transition. You get the idea.

How best to promote these hybrid ideas? Break the oligopoly of our two-party system. Diamond suggests two innovations. First, let every state emulate California’s recent grass-roots initiative that took away the power to design state electoral districts from the state legislature and put it in the hands of an independent, politically neutral, Citizens Redistricting Commission. It will go to work after the 2010 census and reshape California’s state legislative districts for the coming elections. Henceforth, districts in California will not be designed to be automatically Democratic or Republican  so more of them will be competitive, so more candidates will only be electable if they appeal to the center, not just cater to one party. (There is a movement pressing for the same independent commission to be given the power to redraw Congressional districts.)

Second, get states to adopt “alternative voting.” One reason independent, third-party, centrist candidates can’t get elected is because if, in a three-person race, a Democrat votes for an independent, and the independent loses, the Democrat fears his vote will have actually helped the Republican win, or vice versa. Alternative voting allows you to rank the independent candidate your No. 1 choice, and the Democrat or Republican No. 2. Therefore, if the independent does not win, your vote is immediately transferred to your second choice, say, the Democrat. Therefore, you have no fear that in voting for an independent you might help elect your real nightmare  the Republican. Nothing has held back the growth of independent, centrist candidates more, said Diamond, “than the fear that if you vote for one of them you will be wasting your vote. Alternative voting, which Australia has, can overcome that.”

Obama won the presidency by tapping the center  centrist Democrats, independents and Republicans who wanted to see nation-building at home “to make their own lives and those of others better,” said Tim Shriver, the C.E.O. of the Special Olympics. They saw in Obama a pragmatist who could pull us together for pragmatic solutions. But hyperpartisanship has frustrated those hopes. (Alas, though, it is not equal. There are still many conservative Blue Dog Democrats, but the liberal Rockefeller Republicans have been wiped out.) If that radical center wants to be empowered, it can’t just whine. It needs its own grass-roots movement to promote reforms like nonpartisan redistricting and alternative voting in every state. It’s tea time for the center.