There’s not a prayer that comprehensive immigration reform will pass Congress this year, but there’s a slim one that a smaller “down payment” measure might. And it should.

[IMGCAP(1)]Many of the nation’s most important Latino groups, plus Sen. Dianne Feinstein (D-Calif.), are now pushing passage of a package to legalize undocumented workers in the farm industry and young people going to college or the military.

What’s needed now is some concerted leadership — from President Barack Obama, from Republican presidential wannabes (and maybe former Florida Gov. Jeb Bush) and business groups — plus some gumption (and simple humanity) on the part of GOP Senators who have supported immigration reform in the past.

The problem, of course, is lock step GOP opposition to anything Democrats want to do — plus a political atmosphere inflamed by Arizona’s effort to sic its police on illegal immigrants.

Republicans are fixed on a “border security first” immigration strategy, while “down payment” involves legalizing the status of about 2 million undocumented immigrants.

There’s also resistance in the Congressional Hispanic Caucus, many of whose leaders fear that passing an agriculture bill now will pull a key group — the grower lobby — out of the campaign for comprehensive immigration reform.

There’s also fear that Republicans will try to attach harsh enforcement provisions to any “down payment” bill.

Still, it’s worth the effort. “A small, good deal is better than no deal at all,” says Antonio Gonzalez, president of the Southwest Voter Registration Education Project and a convenor of the National Latino Congreso, a coalition of major Hispanic groups.

“We want comprehensive reform, but right now we need a lifeboat,” he told me. “We need to take care of the people we can.”

The National Latino Congreso includes the League of United Latin American Citizens and the Mexican American Legal Defense and Educational Fund.

The “down payment” strategy also has been endorsed by a huge coalition of groups organized as Reform Immigration for America, which includes the National Council of La Raza and the National Immigration Forum.

Senate Majority Leader Harry Reid (D-Nev.) may be interested in pushing only the Development, Relief and Education for Alien Minors Act, but Feinstein wants the AgJOBS bill, too. Her staff counts no more than 56 votes for either measure separately but thinks the farm lobby can pull in enough Republicans to get to 60 for the two measures as a package.

The DREAM Act, co-sponsored by Sens. Dick Durbin (D-Ill.) and Dick Lugar (R-Ind.) would offer legal status to young people brought to the U.S. illegally as children if they go to college for two years or join the military.

AgJOBS, sponsored by Feinstein and Lugar, would offer legal status (a “blue card”) to workers with two years’ experience in agriculture, and to their families, if they agreed to stay in farm work for another two years.

Each of the measures would legalize about 1 million of the 12 million undocumented people in the U.S.

As policy matters, both measures make eminent sense. It’s pure madness that the nation is denied the service of illegal immigrants who want to join the military.

And it’s a waste of human talent — and simple cruelty — to depress the life chances of young people because their parents brought them to the U.S. illegally.

Meantime, up to 75 percent of the people working on farms in the U.S. — particularly picking fruits and vegetables — are here illegally. It’s hot, back-breaking, low-wage work that American citizens almost certainly won’t do.

The AgJOBS bill also would create a channel for foreign farmworkers to enter the U.S. temporarily. About 200,000 now enter illegally each year — and many stay because border enforcement has stiffened.

According to grower organizations, without adequate labor, crops are rotting, farms are closing down and food imports are increasing, costing jobs in farm-related industries.

In the late 1940s and 1950s, when the nation invited temporary farm workers through the bracero program, illegal immigration plummeted. Then it surged when the program was canceled in 1960 owing to union opposition.

In 2004, an AgJOBS bill had 12 Republicans among its 62 co-sponsors, including Sens. Mitch McConnell (Ky.), Orrin Hatch (Utah), Thad Cochran (Miss.) and John Ensign (Nev.).

This year’s bill has only one Republican, Lugar, although there are 11 Republicans in the Senate who have voted for immigration reform in the past. They include retiring Senators such as Judd Gregg (N.H.), George Voinovich (Ohio), Bob Bennett (Utah) and Sam Brownback (Kan.), plus John McCain (Ariz.), Lindsey Graham (S.C.), Susan Collins (Maine), Olympia Snowe (Maine) and Lisa Murkowski (Alaska).

The business community — not only agribusiness, but the U.S. Chamber of Commerce, the Business Roundtable and high-tech industries — ought to lobby Republicans to make a down payment on wider reform that might include more H-1B visas for high-skilled workers and green cards for science graduates.

Republican presidential candidates have an interest in getting the divisive immigration issue “off the table” for 2012 and stopping the party’s hemorrhage of Hispanic voters. So do party luminaries such as Jeb Bush.

Obama ought to be in the lead working on legislative strategy — partly to repair his own reputation with Latinos disappointed at his failure to push comprehensive reform.

The “down payment” strategy will hardly fix America’s broken immigration system, but it’s a step in the right direction.