The wishful scenario many Republicans envisioned after Barack Obama’s change of heart this month on gay marriage—the president’s African-American base, far less supportive of expanding marriage than other parts of his coalition, becomes demobilized or even defects as a result of Obama’s stance—already seems unlikely to be realized. Last Thursday, Public Policy Polling revealed a 36-point swing in black support for gay marriage among Maryland voters, who will have the chance to legalize the practice in a November referendum, since PPP’s last poll on the subject in March. Then, 56 percent had been opposed to the new marriage law and 39 percent supported it. In May, PPP found the numbers nearly reversed: 55 percent supported, and 36 opposed. By all indications, black voters weren’t abandoning Obama over an issue on which they disagreed, but adjusting their opinions to match his.

That notion—that our views toward Obama are stable and everything else is changing around them—has been at the core of Michael Tesler’s groundbreaking survey research throughout the Obama era. Last week, as PPP tracked opinion in Maryland, the Brown University political scientist was reviewing his own national polls conducted since Obama’s switch, which helped moor the movement on gay marriage in a broader, deeper set of attitudes. Not only was Obama’s support pulling blacks toward his position, it was also pushing a segment of whites whom Tesler categorized as “racial conservatives” away from his position. In other words, Obama had such sway over race-conscious voters that they adjusted their positions on gay marriage because of him.

If Tesler was surprised by this, it was only because he believed views on gay marriage would be some of the most stable in politics, deeply anchored in moral values. Since 2009, Tesler has been chronicling what he calls the “racialization” of issues in the Obama era—the extent to which public opinion on topics unrelated to race have taken on a racial cast as Obama has staked out positions on them. Tesler has used polling experiments to identify a series of issues that have become enmeshed in complicated racial attitudes by dint of Obama’s association with them: health care reform, taxes, the nomination of Sonia Sotomayor to the Supreme Court. Even Bo Obama fell into this matrix; racists looked less favorably on a picture of the president’s dog when they learned the identity of his owner. That part, too, surprised Tesler. “I thought people would have stronger views about dogs than politics,” he said.

The 31-year-old’s academic career has taken place almost entirely in the Obama era, and he has begun to assemble a compelling framework for understanding what Obama’s legacy might be, regardless of whether he wins a second term. Tesler’s body of research suggests that instead of delivering what many suggested would be a post-racial presidency, Obama will have polarized corners of American politics previously untouched by race. Not only have racial considerations affected whether voters will support Obama, but they are beginning to renovate the entire architecture of public opinion.

Tesler’s mentor, UCLA psychologist David Sears, introduced the idea that it did not take policies with overtly racial content—like the Civil Rights Act or affirmative action—for racial attitudes to spill over into political views. In 1987, Sears, along with Jack Citrin and Rick Kosterman, published a chapter in the book Blacks in Southern Politics arguing that the mere fact of Jesse Jackson’s presidential candidacy three years earlier (the first competitive one waged by an African-American) had accelerated the polarization of southern politics. Using National Election Study survey data, Sears demonstrated that Southern whites who harbored racial animus (as measured by their evaluations of blacks and views on welfare and school busing) thought less of the Democratic Party after Jackson ran for president. Race was still shaping their views of the contest between two white men, Ronald Reagan and Walter Mondale.

By the time Obama announced his candidacy two decades later, the country appeared to have changed. The overtly racial issues like affirmative action and busing had largely receded from political debates, and what Tesler and Sears called “old-fashioned racism” of the Jim Crow era had all but disappeared from public life. Yet when Tesler and Sears looked at poll data from 2008, they found what much anecdotal reporting from that campaign had suggested: people’s decisions to vote for Obama were linked to their posture on race. Tesler measured this through a “racial-resentment battery” of questions he could add to any political survey—asking respondents if blacks suffered discrimination and whether the country has gone too far pushing for equal rights.

In the past, black candidates had been elected to lesser posts, especially big-city mayoralties, and had seen racially motivated resistance soften over the course of their time in office. Racial animus had been significant predictors of opposition when these candidates first sought office, but as voters saw pioneers like Los Angeles’s Tom Bradley fulfilling their executive duties, they appeared to replace their race-based expectations with personalized judgments rooted in a politician’s performance. But, as Tesler and Sears lamented in their 2010 book Obama’s Race: The 2008 Election and the Dream of a Post-Racial America, that never seemed to happen with the new president. They noted that in Obama’s first 100 days, even as news polls showed him broadly popular (and before Republicans had turned en masse against him), surveys that also measured racial resentment unmasked a deep, nonpartisan divide. In April 2009, the Pew Research Center showed a gap of 70 points in Obama’s approval between “strong racial liberals” and “strong racial conservatives”—more than any of his five most recent predecessors in the White House. “Perhaps the profound racial hopes and fears embodied by our first African-American president have made racial attitudes simply more accessible than they were for local black politicians who did not symbolize such sweeping racial changes,” the authors wrote.

Eight months after the inauguration, Tesler stumbled upon a serendipitous opportunity to see how those racial attitudes were affecting other issues on Obama’s docket. In August 2009, CNN conducted a poll about Sonia Sotomayor’s pending Supreme Court nomination, curiously splitting their sample between two different ways of wording the question. One version mentioned that she had been nominated by Obama, and one didn’t make reference to the president at all. By chance, because the Skip Gates “beer summit” was in the news, in the same survey CNN also asked how common police discrimination was against African-Americans. A respondent’s views on discrimination (on a spectrum of “very common” to “very rare”) was three times more influential on his support for Sotomayor among those who heard Obama’s name compared to those who didn’t.

Tesler started looking for “issues that people don’t have strong feelings about, and issues that weren’t already folded into the current partisan alignment,” as he put it. Obama started feeding plenty of them—the stimulus, health care reform, cap-and-trade, all relatively new issues without firmly established loyalties. Tesler began working with the polling outfit YouGov to match how voters’ changing views on them matched up to their answers to the racial-resentment questions. He found a “spillover of racialization” into health care reform: Voters who heard descriptions of the contrasting components of the 1993 Clinton and 2009 Obama proposals were more likely to grow disapproving of Obama’s when they heard the presidents’ names—as long as they demonstrated racial resentment elsewhere in the survey.

Even presidential pets were viewed through the same lens. Tesler showed 1,000 YouGov respondents a picture of a Portuguese water dog and asked how favorably they felt toward it. Half saw the dog introduced as Bo Obama, and half as Ted Kennedy’s dog, Splash. (Both political dogs are the same breed, but the picture was of Obama’s.) Those with negative feelings toward blacks thought less of Obama’s dog.

The latest issue to fall into this pattern is gay marriage, although PPP’s Maryland findings seem to confirm that racialization can work in multiple directions. Tesler has repeatedly found that the polarization he has documented is partly a function of the voters he describes as “racial liberals”—those who score low on the resentment battery, a category that includes blacks and progressive whites—being more likely to support a policy when they learn that Obama does, too.

That’s one reason why Tesler, who does not hide his Obama sympathies, was cheered by the White House’s recent decision to embrace the epithet “Obamacare” in campaign-season communications, after years of dismissing the term. “I think health care is forevermore ‘Obamacare,’ ” Tesler said last month on the sidelines of the Midwestern Political Science Association conference in Chicago, a few blocks from Obama’s campaign headquarters. Voters who were against Obamacare opposed it for such deeply ingrained reasons that no number of ads about the bill’s provisions could change their minds, Tesler believed, but Obama had yet to benefit from racialized attitudes on the issue spilling over his way. “Why not try to get the mojo going for their side, too? People who are against it are against it. You might as well use it to motivate your side.”

Indeed, the only mistake the White House may have made in embracing policies that cut against those held by parts of the Democratic base—against white liberals on military tactics, or blacks on sexual politics—was in failing to have Obama personally embrace those positions as his own. White liberals and blacks are as primed to support what he believes as racists are to oppose it, and a new Democratic orthodoxy is lining up behind him. Win or lose in November, this may be Barack Obama’s party for a long time.