HARRISBURG, Pa. (AP) — Vice President Kamala Harris and former President Donald Trump will take their fight for Pennsylvania to opposite ends of the state on Monday, with Harris speaking in the northwest corner in Erie and Trump in the southeastern suburbs of Philadelphia.

Democrat Harris and Republican Trump have been making regular appearances in what is the country's largest battleground state — it will be Harris' 10th visit to Pennsylvania this campaign season, and just last week Trump made stops in both Scranton and Reading.

Pennsylvania's energy industry and natural gas fracking are likely topics as they compete for the fraction of the state's voters who have not made up their minds. Mail-in voting is well underway in the state where some 7 million people are likely to cast votes in the presidential race.

Trump beat Hillary Clinton by more than 40,000 votes in Pennsylvania on his way to winning the presidency in 2016, but native Scrantonian Joe Biden beat Trump by about 80,000 votes in the state four years ago.

Harris will be holding a rally in Erie, a Democratic majority city of about 94,000 people bordered by suburbs and rural areas with significant numbers of Republicans. Erie County is often cited as one of the state's reliable bellwether regions, where the electorate has a decidedly moderate voting record. Trump visited Erie on Sept. 29.

Harris plans to talk up early voting during her rally. And she'll stop by a Black-owned small business in Erie in advance of the rally to promote her proposals to give Black men more economic opportunities and other chances to thrive as Democrats try to energize the voting bloc.

Trump plans a town hall Monday at the Greater Philadelphia Expo Center and Fairgrounds in suburban Oaks, hoping to drive up turnout among his supporters.

Pennsylvania and its 19 electoral votes, the most of any swing state, have generated the most attention by far from the Democratic and Republican presidential campaigns. Including Monday's scheduled events, they will have made 46 stops in the state, according to Associated Press tracking of the campaigns' public events.

Michigan, with 33 visits, and Wisconsin, with 29, are the next most-visited states, illustrating how both campaigns are focusing on winning states that had been part of the Democrats' so-called "blue wall" until Trump emerged as the Republican standard-bearer.

Democrats have won three straight elections for governor, and both current U.S. senators are Democrats, but the state's legislature is closely divided.