More than 20 guests are sitting with U.S. first lady Michelle Obama Tuesday as President Barack Obama delivers his third State of the Union address before Congress.

Among the invitees are Laurene Powell Jobs, the widow of late Apple founder Steve Jobs and founder of her own organization helping underserved communities, and astronaut Mark Kelly, whose wife, retiring U.S. Congresswoman Gabrielle Giffords, was seriously wounded last year in a shooting spree in her home state of Arizona.

In support of Mr. Obama's comprehensive tax reform, billionaire financier Warren Buffett's secretary, Debbie Bosanek, will also sit with the first lady to highlight Buffett's complaint that his staff pays a higher rate on taxes than he does.

The White House says the mayor of San Antonio, Texas and several members of the military will also be in attendance.

Not all of those invited are well known. The White House says other guests include an automobile factory manager, a small business owner who returned overseas jobs to his home state, an immigrant entrepreneur, an elementary school teacher and a university student.