The victory of Tea Party favorite Ted Cruz in the Republican Senate primary election in Texas on Tuesday over the state’s lieutenant governor David Dewhurst, considered the establishment’s choice for November’s election, signals a potentially worrying trend for the state’s Republicans. The radicalization of their party coupled with changing demographics could prove an opportunity for Democrats to rebound in what is otherwise considered a Republican stronghold.

There weren’t many policy differences between Cruz and Dewhurst, if there were any at all. Both oppose abortion, gay marriage and support a balanced budget amendment to the United States . But the former successfully managed to taint his opponent as a moderate, willing to compromise with Democrats in Congress.

Cruz will go up against Democrat Paul Sadler in the fall but is widely expected to win the race because of his state’s strong Republican leanings.

It wasn’t until the 1980s that Texas became a Republican bulwark. The Democratic Party used to dominate politics in the South, stemming from its history as the party of segregation when Republicans were viewed a northeastern elitists who banned slavery and imposed Reconstruction on the states that had attempted to secede from the Union in the Civil War.

From the 1960s onward, however, the Democratic Party moved to the left while the Republican Party became more conservative. It almost completely controls government in Texas now.

That won’t quickly change even if President Barack Obama told Texans in San Antonio last week that, “you’re not considered one of the battleground states although that’s going to be changing soon.” Longer term, he may be proven right though.

In a recent blog post, former Republican Party presidential candidate and conservative commentator Pat Buchanan points to the demographic changes that are working against the Republican Party in Texas as they are across the country.

Hispanic Americans, who voted two to one for Obama in the 2008 election and three to two against George W. Bush in 2004, formed 7.4 percent of the electorate four years ago but comprise 15 percent of the population. “Both percentages will inexorably rise,” predicts Buchanan, as a result of higher birth rates and immigration.

Buchanan ascribes Hispanic voting behavior to the fact that they disproportionately benefit from government programs. “Why should poor, working- and middle-class Hispanics, the vast majority, vote for a party that will reduce taxes they don’t pay but cut the benefits they do receive?”

The Republican Party could have an advantage in that Hispanic voters, many of them Catholics, are more socially conservative than other Democratic constituencies but its usually strong positions on inhibiting immigration could scare them off.

Tea Party candidates, while primarily focused on debt and deficit reduction, are also more adamant about limiting immigration and securing the Mexican border than the Republican Party used to be. They praise legal immigration but simultaneously denounce illegal migrants, 75 percent of whom hail from Latin American countries, and have volunteered no plans for expanding legal entry to the United States.

The Tea Party is also highly critical of government welfare programs like food stamps, Medicaid and unemployment insurance which racial minorities rely on in relatively higher numbers than whites. If the Republican Party is to appeal to Hispanic voters, which it has to, not so much in Texas yet but certainly in Florida, to win national elections, it seems that it should move in the very opposite direction from Tea Party’s.

Buchanan notes that of the seven largest states in the country, California, New York and Illinois appear “lost” to the Republican Party. “Pennsylvania has not gone Republican since 1988. Ohio and Florida, both crucial, are now swing states. Whites have become a minority in Texas.”

The second largest state in terms of population, Texas wields 38 electoral votes in the 2012 presidential election. It is eclipsed only by California, which has fifty-vote votes and hasn’t voted for a Republican since George H.W. Bush ran in 1988.

“When Texas goes,” writes Buchanan, “America goes.”