In the final stretch, Trump and Harris go to Pennsylvania more than any other battleground

Want to know which state is the most critical to both former President Donald Trump's and Vice President Kamala Harris' path to the White House? Just check where they've made the most visits: Pennsylvania.

Since Harris entered the presidential race in July, she and Trump, along with their running mates — Minnesota Gov. Tim Walz and Ohio Sen. JD Vance — have made Pennsylvania their most-visited state for campaign stops across the battleground map.

As NBC News mapped out, both campaigns have blanketed the state in recent months, with their presidential and vice presidential nominees making about 50 appearances over the past three months, easily the greatest total of any swing state.

The campaign's dollars are flowing into Pennsylvania too. One of every four dollars spent on ads in the presidential race from Sept. 1 to 20 were spent in the state, according to AdImpact.

Pennsylvania offers the most Electoral College votes among the hotly contested states. Recent surveys have found the overall race in Pennsylvania to be within the margin of error for polls, with a survey from Quinnipiac University this month finding Harris up 3 percentage points, a Philadelphia Inquirer/New York Times/Siena College survey finding her up 4 points and The Wall Street Journal having Trump up 1 point.

President Joe Biden narrowly won the state in 2020 while Trump pulled out a razor-thin win in 2016.

(Editor's note: The map includes campaign stops and planned campaign appearances through Saturday, Oct. 19. It will continue to be updated as more appearances are made.)