Kamala Harris looked glad to be back at her alma mater, Howard University in Washington. “The first office I ever ran for was probably the most difficult campaign I’ve ever been in,” she recalled with laughter, “and that was freshman class representative of what was then called the liberal arts student council.”

The US vice-president had returned to this historically Black university on Thursday for a difficult campaign of a different nature: protecting voting rights from a Republican onslaught. It is just one test for a potential future president burdened by heavy expectations and already gaining detractors inside and outside the White House.

As the daughter of immigrants from Jamaica and India, Harris, 56, is the first woman and first woman of color to serve as vice-president. She is also deputy to the oldest president in American history – Joe Biden is 78 – creating a heightened sense that she is heir apparent. That puts her every move under the microscope. “She’s holding up and is excited about all of the challenges ahead,” said Donna Brazile, former interim chair of the Democratic National Committee (DNC), who gave Harris what she called a “big sister” hug at the Howard event.