Gov. George W. Bush stunned the political world six years ago with the first Spanish-language television advertisement by a presidential candidate in a party primary. “Es un nuevo dia,” he said in the spot that ran on the eve of Arizona’s Republican primary in 2000. Translation: “It is a new day.”

Looking now over the ruins of his pro-immigration agenda, today the second-term president might say something quite different about his erstwhile outreach to Hispanic voters: “No mas.”

No more do we hear boasts about the Bush electoral strategy to solidify southern border states for the GOP with Big-Tent appeals to the ever-expanding rolls of naturalized voters. Instead, Republicans on Capitol Hill are headed the other direction, stressing tough enforcement and all but ignoring Bush’s ideas for guest-worker programs and other changes meant to ease the way for immigrants.

The demise of Bush’s pro-immigration agenda within his party stems from three things: a dramatic rise in illegal immigration to Republican strongholds in the South; the xenophobic tendencies unleashed by the Sept. 11 attacks on U.S. soil; and, finally, its political failure. It did little to boost the numbers of naturalized Americans voting Republican.

Bush’s life as a businessman and governor in Texas, as well as his fluency in Spanish, are credited with driving his ambition to be remembered as an immigration reformer. As a first-time presidential candidate, and in the early days of his administration, it was one of the few foreign affairs issues that he felt secure about. On most others, he needed daily tutoring by Condoleezza Rice and others. His views on immigration also fueled his friendship with Mexican President Vicente Fox, whose down-to-earth political style he often compared with his own.

And, as conservative critics of Bush’s immigration views often note, his agenda is in sync with his corporate supporters, many of whom favor easing immigration laws as a path to cheap labor. That’s not a factor much stressed by the Bush administration, except at private fundraisers.

Back in 2000, the president’s political team, led by Karl Rove, often bragged to reporters about how Bush’s “Hispanic strategy” would one day be regarded as visionary, and at least as effective as Richard Nixon’s “Southern strategy” in opening up wide swaths of fresh terrain for the Republican Party. But even in that election, after so much effort by the Bush campaign to appeal to Hispanics, Democrat Al Gore bested Bush among that group, 62 percent to 35 percent, according to exit polls. That was only a slight improvement over the GOP’s historical average, and not enough to swing states, such as New Mexico, to the Republican column.

Those unimpressive results might have been due in part to the surprising reaction of Hispanics to Bush’s immigration proposals. Opinion surveys consistently show that fewer than expected actually favor more immigration. A Gallup Poll in 2004 found that a plurality (39 percent) of Hispanic voters want to decrease the level of immigration.

Still, there was hope for Bush’s Hispanic strategy after the 2004 election. Exit polls showed his support among that demographic increased 9 points, to 44 percent. Some analysts dispute that figure, insisting it was closer to 40 percent, but even that enhanced showing, plus adding New Mexico to the GOP column, failed to persuade congressional chiefs to follow the president’s lead. Many attributed the 2004 Hispanic vote more to Kerry’s awkwardness with Latinos on the stump than to Bush’s increased popularity.

In the end, Bush’s Hispanic strategy does not seem destined to build on Nixon’s Southern strategy for Republicans. In some ways, the tactics even collided, proving to be almost mutually exclusive — and now forcing congressional Republicans to assuage conservatives, especially in the South, who are outraged by what they see as the president’s liberal pandering to illegal immigrants.

Once again, Bush’s political advisers have failed to calculate the passions of his conservative base — and they know it. “We should have led in the beginning with an enforcement agenda on immigration,” says one White House consultant, who compares the slip-up to their misreading of the reaction to the Dubai port sale fiasco and to the hostility of abortion foes to the Supreme Court nomination of Harriet Miers.

Those previous setbacks were overcome by immediate capitulation to the conservative base. But on immigration, Bush is more likely to press on and struggle mightily to realize his dream for a legacy of real change in how we treat foreign nationals.

For now, look for the White House to indulge the Republican move on Capitol Hill to get tough with illegal immigrants and hold the conservative base for the midterm election. But afterward, expect Bush to try again.

That “new day” from six years ago could live again.

Contributing Editor Craig Crawford is a news analyst for MSNBC, CNBC and “The Early Show” on CBS. He can be reached at ccrawford@cq.com.