All eyes are on Philadelphia with Harris, Vance visits

A new phase in this historic presidential election cycle starts Tuesday in America's birthplace.

Why it matters: Vice President Kamala Harris ' and former President Donald Trump 's campaigns are all-in on Pennsylvania — and today is a shining example.

State of play: Harris will make her first appearance with her yet-to-be-announced running mate at Temple University's Liacouras Center in North Philly Tuesday.

• The rally will kick off a five-day, seven-city tour of battleground states, including visits with voters in more intimate settings like union halls, family-owned restaurants and campaign field offices.
• Harris' team also plans to kick off a " Republicans for Harris " campaign in Pennsylvania this week — aiming to win over GOP voters who aren't sold on Trump, the AP reports.

Meanwhile, Trump's running mate Sen. JD Vance (R-Ohio) is also traveling to Philadelphia Tuesday. He's speaking at an event at the 2300 Arena in South Philly around noon, the Trump campaign told the Inquirer .

• Vance is planning to tour the same states as Harris this week, Politico reports.

The big picture: The White House will likely be won in Pennsylvania, the largest swing state.

• That's part of the rationale behind why many think Harris could pick Pennsylvania Gov. Josh Shapiro as her VP.

What we're watching: The Trump and Harris campaigns are set to spend more than double on advertising in Pennsylvania than in any of the other six swing states, per an Axios analysis of AdImpact data.

• Collectively, that's at least $210 million in the eight months between the end of the Republican primary and Election Day, according to past spending and future bookings.

Go deeper: What the possible loss of Josh Shapiro could mean for Pennsylvania

• Who becomes Pennsylvania's governor if Josh Shapiro becomes VP contender