WHEN thinking about the state of the Republican Party, I defer to a point that the Democratic consultant James Carville made the other day: “When I hear people talking about the troubled state of today’s Republican Party, it calls to mind something Lester Maddox said one time back when he was governor of Georgia. He said the problem with Georgia prisons was ‘the quality of the inmates.’ The problem with the Republican Party is the quality of the people who vote in their primaries and caucuses. Everybody says they need a better candidate, or they need a better message but — in my opinion — the Republicans have an inmate problem.” The political obsessions of the Republican base — from denying global warming to defending assault weapons to opposing any tax increases under any conditions, to resisting any immigration reform — are making it impossible to be a Republican moderate, said Carville. And without more Republican moderates, there is no way to strike the kind of centrist bargains that have been at the heart of American progress — that got us where we are and are essential for where we need to go.

Republican politicians today have a choice: either change your base by educating and leading G.O.P. voters back to the center-right from the far right, or start a new party that is more inclusive, focused on smaller but smarter government and market-based, fact-based solutions to our biggest problems.

But if Republicans continue to be led around by, and live in fear of, a base that denies global warming after Hurricane Sandy and refuses to ban assault weapons after Sandy Hook — a base that would rather see every American’s taxes rise rather than increase taxes on millionaires — the party has no future. It can’t win with a base that is at war with math, physics, human biology, economics and common-sense gun laws all at the same time.

Do you know how troubled this party is? Two weeks ago, the former G.O.P. Senate majority leader Bob Dole, a great American, went to the Senate floor in his wheelchair to show his support for Senate ratification of the U.N. Convention on the Rights of People With Disabilities. Nevertheless, the bill failed to win the two-thirds needed for ratification, because only eight Republicans dared to join Democrats in support of the treaty, which was negotiated and signed by George W. Bush! It essentially requires other countries to improve to our level of protection for the disabled, without requiring us to change any laws. It has already been ratified by 126 countries. But it failed in the Senate because Rick Santorum managed to convince the G.O.P. base that the treaty would threaten U.S. “sovereignty.” Santorum stopped just short of warning that space aliens would take over our country if we ratified the treaty.

Because they control the House, this radical Republican base is now holding us all back. President Obama was moving to the center in these budget negotiations. He reduced his demand for higher tax revenues to $1.2 trillion from $1.6 trillion; he upped the level at which Americans who would be hit with higher taxes to those earning $400,000 a year from $250,000; and he made his own base holler by offering to cut long-term spending by lowering the inflation adjustment index for Social Security. It seemed that with a little more Republican compromise, Obama would have met them in the middle, and we could have had a grand bargain that would put the country on a sounder fiscal trajectory and signal to the markets, the world and ourselves that we can still do big hard things together. That will have to wait. Now the best hope is some mini-, crisis-averting, Band-Aid.

The G.O.P. today needs its own D.L.C. The Democratic Leadership Council was founded by a group of Democratic governors and activists, led by Bill Clinton, in 1985 to lead the party back to the center from a failing leftward course that had resulted in it being repeatedly shut out of the presidency, except after Watergate. I asked Clinton’s pollster, Stan Greenberg, what Republicans could learn from the Clinton/D.L.C. experience.

“There is a lot of pain,” said Greenberg. “You can’t change the party without pain. You can’t just make some head-fakes to Hispanics.” The D.L.C., he noted, started by building an organization over 10 years and by running more centrist Democrats “in the primaries.” It didn’t just wait to pivot to the center in the general election. It fought for and educated the Democrat base in the primaries, by D.L.C. candidates running in support of free trade, Nafta and welfare reform. “With Clinton, we won the primaries in a way that defined us, so that he could run in the general election as the candidate of broad appeal.” That fractured the party and produced Ralph Nader, which cost Al Gore the 2000 election. But after losing that election, said Greenberg, the Democrats came together around a moderate-left core and did not engage “in dysfunctional primaries.”

Republicans need to go through a similar process of building new institutions and coalitions to support candidates who can move the party back to the center-right. Today, all their institutions, from think tanks to Fox TV, said Greenberg, “are reinforcing the trends that are marginalizing their party.”

Unfortunately, we don’t have a decade to wait for a G.O.P. D.L.C. Some leaders in that party need to stand up for sane compromises right now.