Eight years ago, the U.S. economy was languishing. We were bogged down in two wars, and the national debt was rising. President Bush was up for re-election, and Republicans needed a wedge issue. They found it in Massachusetts, whose Supreme Judicial Court in 2003 had asserted a statewide right to gay marriage. Seizing the opportunity, Massachusetts Gov. Mitt Romney ran around the country declaring a national moral crisis. Republicans, urged on by Bush, introduced a constitutional amendment to prohibit gay marriage.

On June 18, 2004, Sen. John Cornyn, R-Tex., the subcommittee chairman entrusted with the amendment, joined two colleagues at a press conference to promote it. Cornyn declared gay marriage an economic issue:

We know from some of the social experimentation that’s occurred in Scandinavia and elsewhere that when same-sex couples can legally marry, that essentially what happens is people quit getting married across the board, and more people raise children outside of marriage at higher risk for a whole host of social ills, placing additional burdens on the government and the taxpayers that support that government.

A reporter asked the senators about Democratic complaints that the GOP was “playing divisive election-year politics.” Cornyn brushed off the idea. “I don’t think it is a particularly divisive issue,” he replied. “I think, when the American people get a chance to have their voice heard, that they will overwhelmingly reaffirm their commitment to traditional marriage.”

Four days later, Cornyn and other members of the Senate Judiciary Committee held a hearing on the marriage amendment. Romney flew down to be the lead witness. Sen. Russ Feingold, D-Wisc, called it “a politically motivated exercise” and pointed out that the country was “struggling every day with so many more pressing issues.” Romney disagreed:

I want to spend my time devoted to working in our schools and helping our kids, finding ways to provide more prescription benefits for our senior citizens, doing a better job to provide a stronger economy and more jobs to our citizens. Those are our highest priority. But when our Supreme Judicial Court acted, they brought forward a change in a definition of an institution which is fundamental to my state, fundamental to our nation. And in order to preserve the rights of respective states to set their own policies with regards to marriage, I believe this amendment, or one of a similar nature, is necessary.

A month later, when Democratic senators condemned the amendment as “divisive” and “the politics of mass distraction,” Romney insisted in a CNBC interview that politicians must be put on the record:

A lot of big things are going on. But for some people, myself included, how children are going to be raised in the next generation and the one after that is also important, and it’s worth discussing and having politicians have to vote on. Most politicians don’t want to you know where they stand on that issue. And I think it’s appropriate for us to know where people stand.

That was 2004. Eight years later, Cornyn is the chairman of the National Republican Senatorial Committee, Romney is the party’s de facto presidential nominee, and both men are singing a very different tune. Last Thursday, after President Obama endorsed same-sex marriage, Romney ducked an invitation on Fox News to challenge the president. “Even within my party, there are people who have differing views on this point,” Romney cautioned. “The Republican Party does not consist of people who all have the same views on all the issues.” The next day, Romney dodged another reporter’s bait: “I just don’t think this becomes a hot political issue dividing our nation. Instead, I believe that we should respect the viewpoints of various people and move on.”

On Sunday, CNN anchor Candy Crowley asked Cornyn, “Is this something that you think Mitt Romney ought to bring up frequently?” Cornyn deflected the question: “President Obama brought this issue up because … he’s trying to raise divisive issues up to solidify his base and to divide the country, and that isn’t what we should be focusing on now. We should be focusing on jobs and the economy.”

It’s hard to believe these are the same guys who were whooping it up about gay marriage in 2004. What happened?

To answer that question, look at the polls. In 1996, when Republicans campaigned successfully for a federal law against gay marriage, most Democrats opposed the legality of same-sex marriages. They rejected the idea by approximately 60 to 33 percent in Pew and Gallup surveys. Independents closely matched that split. Republicans opposed gay marriage even more strongly, by about 80 to 15 percent in both polls.

In 2004, Republicans were still firmly set against gay marriage. Their margin of opposition was 80 to 19 in Gallup’s May survey, 78 to 17 in Pew’s combined annual data, and 73 to 24 in a February Washington Post/ABC News sample. The margin of opposition among independents, however, had declined considerably. It was 53 to 37 in Pew’s data, 52 to 44 in the Gallup poll, and 48 to 44 in the Post survey. Democrats, meanwhile, were now roughly split. In February, the Post found them evenly divided, 48 to 47 percent. A later Post survey, taken in August, found them opposed by 52 to 43 percent. Pew’s yearly average showed them opposed by 50 to 40 percent, while Gallup’s May sample had them favoring gay marriage by 51 to 46 percent.

Since then, public opinion has continued to shift toward accepting gay marriage. Democrats now support it by margins of 64 to 32 in the Post’s March 2012 survey, 65 to 34 in Gallup’s May sample, and 59 to 31 in Pew’s combined 2012 data. Independents in all three polls now favor gay marriage: 54 to 42 according to the Post, 52 to 38 according to Pew, and 57 to 40 according to Gallup. At the same time, the Republican margin of opposition has fallen. It’s 74 to 22 as measured by Gallup, 68 to 23 as measured by Pew, and 57 to 39 as measured by the Post.

Republicans aren’t split as deeply as Democrats were in 2004. Nor are Democrats as united today as Republicans were back then. And if you look at polling data over time, you’ll see that public opinion has lurched or backtracked along the way. Just last night, CBS and the New York Times released a sample that leans further to the right.

But overall, the trend is clear. Democrats, who initially opposed gay marriage and then were evenly divided, are gradually uniting in favor of the idea. Republicans, who used to be united against gay marriage, are becoming more closely divided. And independents, who used to lean against gay marriage, now lean toward it. In 2004, if you raised gay marriage as a wedge issue, you divided Democrats, united Republicans, and pushed most independents to the right. Today, if you raise gay marriage as a wedge issue, you divide Republicans, unite Democrats, and push most independents to the left.

That’s why Romney and other Republicans who loved to talk about gay marriage in 2004 now call Democrats divisive for bringing it up. Republicans are happy to divide the country. But they no longer like the way this issue cuts.

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