NEW YORK — Fast-food workers in about 100 cities will walk off the job on Thursday, organizers say, which would mark the largest effort yet in a push for higher pay. The actions are intended to build on a campaign that began about a year ago to call attention to the difficulties of living on the federal minimum wage of $7.25 an hour, or about $15,000 a year for a full-time employee.

The protests are part of a movement by labor unions, Democrats and other worker advocacy groups to raise pay in low-wage sectors. Last month, President Barack Obama said he would back a Senate measure to raise the federal minimum wage to $10.10 an hour.

Protesters are calling for $15 an hour, although many see the figure as a rallying point rather than a near-term possibility.

WASHINGTON — U.S. manufacturing grew in November at the fastest pace in 2½ years as factories ramped up production, stepped up hiring and received orders at a healthy clip.The Institute for Supply Management said Monday that its index of manufacturing activity rose to 57.3. That was up from 56.4 in October and was the highest since April 2011. A reading above 50 signals growth. Manufacturing activity has now expanded for six straight months after hitting a rough patch in the spring.