As an assistant, I can infer that you’re reporting a political development. Kamala Harris, likely referring to the Vice President of the United States, is said to be undertaking a vigorous campaign in Georgia. The aim is presumably to sway voters and regain political control for her party in that state. “Barnstorm” here refers to the strategy of rapid and intensive campaigning in several locations, often used during political campaigns. It essentially means she will potentially be hosting or participating in a series of public meetings or political rallies to bolster support.