By Mark Willen, Senior Political Editor August 13, 2009 President Obama seems to relish a big challenge, so it's no surprise that he still hopes to pass an overhaul of immigration law next year. But it may have been the understatement of the decade when he conceded Monday that it won't be easy. "Am I going to be able to snap my fingers and get this done?" he asked rhetorically at a press conference in Guadalajara, Mexico. "No....There are going to be demagogues out there" who try to block any pathway to legalization for illegal immigrants already in the U.S. In the immortal words of Sarah Palin, "You betcha."Obama promised his Mexican hosts at a short summit this week that he would work for a comprehensive immigration bill, trying to get legislation ready this year for passage next year. Try he will, and for all sorts of reasons. One is that he believes it's in the long-term interests of the U.S. economy, and many employers and business groups agree. Second, he believes it's the humanitarian thing to do, and many Democrats agree. Third, he made a promise to Hispanic groups that helped elect him and that are crucial to the election hopes of several Democrats next year. Advertisement But immigration reform won't be any easier than when Bush tried to do it three years ago. In fact, it may be harder. Having a larger number of Democrats in Congress gives Obama a bigger pool of potential votes, but without the a top Republican like Bush to give Republicans cover, it'll be much harder to reach a bipartisan agreement. Republicans desperately need to improve their standing with the growing number of Hispanic voters, but their mass opposition to the nomination of Supreme Court Justice Sonia Sotomayor suggests many believe the cause is hopeless. They'd rather keep the base happy than expand the election pool. What's more, Obama suffered a big tactical blow when Republican Sen. Mel Martinez of Florida decided to quit early. That deprives the president of his strongest Republican ally. He now has to depend on Sen. John McCain. McCain is a longtime suporter of an immigration overhaul, but he's unpredictable and is sure to exact a price for his cooperation. By acknowledging that passage of a bill this year is impossible, Obama was, of course, just restating the obvious. Congress' agenda is much too full to allow consideration of still another major controversy this fall. But putting it off until next year -- an election year -- makes passage very iffy, and legislation may well have to wait until 2011. Immigration -- particularly what to do about the 12 million illegals already living in the U.S. -- is as controversial as ever, with conservatives vehemently insisting that any path to legalization -- even with stiffl penalties included -- amounts to amnesty. It may have been moved to a back burner on right-wing talk shows by the health care debate, but the issue hasn't disappeared, and it'll come back with a vengeance. Consider that at a town hall meeting in Pennsylvania Tuesday, Sen. Arlen Specter was asked to promise that he wouldn't support a health care bill that provided coverage to illegals. Never mind that most illegals who can't afford coverage are treated free in hospital emergency rooms now. Advertisement Ultimately, a comprehensive bill will pass only if employer groups decide it is a necessary way to assure a supply of legal workers. The Obama administration is indirectly working toward that by taking a hard line in prosecuting employers that knowingly hire illegals and to tighten up border controls. It's less of a problem now, when unemployment is so high, but someday the shortage of legal workers for certain jobs will again become a big problem for businesses.