Money and politics don't always make for polite conversation, but President Obama tried to tackle both at the White House on Tuesday.
Obama signed a pair of executive orders aimed at encouraging conversation about men's and women's pay scales. It's a talk that Democrats hope will yield political gains this year.
It also raised questions, though, about how the administration pays its own people.
Standing before a crowd of women in the White House East Room, President Obama noted that the average woman working full time in America makes just 77 cents for every dollar earned by a man. In 2014, he said, that's an embarrassment.
"Equal pay is not just an economic issue for millions of Americans and families. It's also about whether we're willing to build an economy that works for everybody, and whether we're going to do our part to make sure our daughters have the same chances to pursue their dreams as our sons," he said.
Obama was joined at the event by Lilly Ledbetter, who became a national symbol of unequal pay. She spent years working for a Goodyear plant, all the time making less than her male colleagues.
"I didn't know I was being paid unfairly. And I had no way to find out," Ledbetter said.
Goodyear, like many companies, barred workers from talking about how much they made. Today the president signed executive orders preventing such rules at federal contractors, and directing the Labor Department to gather summary data about contractors' pay scales.
In its effort to shine a spotlight on pay disparity, though, the White House itself got caught in the glare. Spokesman Jay Carney went on the defensive when reporters asked why women working at the White House make less on average than their male colleagues.
"Men and women in equivalent roles here earn equivalent salaries. We have two deputy chiefs of staff, one man and one woman, and they make the same salary. We have 16 department heads. Over half of them are women. All of them make the same salaries as their male counterparts," Carney said.
Carney suggests the disparity in White House pay results from a concentration of women on the lower rungs of the government's pay scale. Cornell University economist Francine Blau says such occupational differences also explain about half the national pay gap between men and women.
"Women are heavily concentrated in health and education, for example. Men are more likely to be in manufacturing, construction. So those types of differences do affect pay rates," she says.
Obama acknowledged the need to help more women into high-paying occupations such as engineering and computer science. Blau, who studies the pay gap with her colleague Lawrence Kahn, says another factor is workplace experience.
"Traditionally a woman might have worked for a while, then she might have dropped out of the labor force when she had children. She might have returned later. And gender differences in experience have traditionally been an extremely important factor in explaining the gender pay gap," she says.
Blau says time spent off the job still explains about 10 percent of the pay gap, even as more women with children stay in the workplace. But a big part of the gap remains a mystery.
"Even when you take into account all the factors that we can measure at least, 40 percent of the gap was unexplained," she says.
While overt gender discrimination has declined over the years, Blau says women may still be penalized in the workplace by subtle, even unconscious factors.
With an eye toward mobilizing working women, the Democratic-led Senate will vote Wednesday on a bill to give women stronger remedies against pay discrimination. Republicans, like Rep. Cathy McMorris Rodgers, have denounced the move as a political ploy.
"On this equal pay day, I would urge us to stop politicizing women and let's start focusing on those policies that are actually going to help women and everyone have a better life," Rodgers said.
But Obama and his fellow Democrats seem determined to keep people talking about the pay gap. "Pay secrecy fosters discrimination," the president said. He wants pay scales everywhere to be as public as those inside the White House.