The world has a way of intruding on Democratic presidential campaigns. Although Sens. Barack Obama and Hillary Rodham Clinton have cast skeptical eyes on trade liberalization, opposing a pact with Colombia and calling for a rewrite of the North American Free Trade Agreement, their aides have been sending different signals.

In Obama’s case, one of his economic advisors told Canadian diplomats that his attacks on NAFTA are essentially campaign rhetoric and cooler heads will prevail on trade after the election. Clinton’s strategist was dismissed this week after it was revealed that he met with Colombia officials to talk about building support for that agreement, in his non-campaign role as head of a major public relations firm in Washington.

Despite fierce denunciations of trade on the campaign trail, we can’t be sure what kind of globalization policies Obama or Clinton would pursue in the White House.

The approach they would take on labor law is transparent. Neither they nor their aides waiver on backing the union agenda. The latest example comes from Obama.

He owes his lead in the polls and in fund-raising in large part to his soaring oratory. He says that words matter.

His language couldn’t have been clearer in an April 2 speech to the Pennsylvania AFL-CIO. He promised to change a system in Washington in which “corporate lobbyists use their clout to shape laws to their liking.”

He vowed to stand up for American workers and “play offense” for “a decent wage … retirement security … (and) universal health care.”

He also pledged to move the ball down the field for organized labor and back its top priority—legislation that would facilitate unionization.

“If a majority of workers want a union, they should get a union,” he said. “It’s that simple. Let’s stand up to the business lobby that’s been getting their friends in Washington to block card check. I will make it the law of the land when I’m president of the United States of America.”

The only thing likely to stand in the way of making that campaign promise a reality is a dwindling cadre of Republican senators. The Senate GOP may barely number enough to sustain a filibuster by the time the party loses several seats in November.

The business lobby argues that the so-called card-check bill would rob workers of the right to a secret-ballot election monitored by the National Labor Relations Board. But a Democratic member of that panel says that the Republican-majority board has been too sympathetic to management during the Bush administration.

In Senate testimony last week, NLRB commissioner Wilma Liebman previewed what may be in store next year for labor law, when Democratic majorities will be stronger on Capitol Hill and a Democrat might occupy the White House.

She cited rising income inequality as a reason for Congress to consider changing the National Labor Relations Act.

“I would welcome comprehensive re-examination of a law that has not been substantially revised for more than 60 years,” she said.

Liebman may get her wish, if Obama becomes president. Some of his opponents have accused him of not outlining specific policy amid his moving oratory. When it comes to labor law, however, Obama is precise. What you hear is what you will get.