Employees and supporters demonstrate outside of a Wendy's fast-food restaurant to demand higher pay and the right to form a union on July 29, 2013 in New York City. Across the country thousands of low-wage workers are again walking off their jobs today protesting for a $15 an hour living wage. - 

Today, fast-food workers in cities across the U.S. are walking off the job. They're calling for a raise in their wages to $15 dollars an hour. Meanwhile, President Obama invoked a similar theme in a speech he gave yesterday that made the case for increasing the minimum wage. 

In his speech, President Obama discussed minimum wage in the broader context of what is happening to the middle class in America today. He talked about how a lot of good paying jobs, especially in manufacturing, are being replaced by minimum wage service sector jobs. And he pointed out that the federal minimum wage is so low today compared to the cost of living that it's hard for many American families to make ends meet. At one point, Obama even gave a shout-out to the striking fast food workers.

The president took great pains to frame his argument in a bipartisan way, referencing Abraham Lincoln and even paraphrasing the father of conservative thought, Adam Smith.

Meanwhile, Senate Democrats are about to begin a push to raise the federal minimum wage to $10.10 an hour over the next few years. In a recent CBS News poll, two-thirds of Americans -- including more than half of Republicans -- said the federal minimum wage should be higher.

The restaurant industry says an increase would push them to downsize their work forces. 

Follow Krissy Clark at @@kristianiaclark