Former US vice president Joe Biden arrives at a rally organized by UFCW Union members to support Stop and Shop employees on strike throughout the region at the Stop and Shop in Dorchester, Massachusetts, on April 18, 2019.

And with a sprawling field of at least 20 Democrats in the running for the party's nomination, Pennsylvania might even prove to be a major state in the primary fight, where it has historically played a smaller role .

While Biden will travel to a slew of other states in his first month on the trail, the extra focus on Pennsylvania shows the Democratic frontrunner trying to shore up his support in a crucial swing state that his party's last presidential nominee, Hillary Clinton, narrowly lost in the 2016 election.

On Thursday, the 76-year-old former vice president for President Barack Obama officially launched his campaign to challenge President Donald Trump for the White House in 2020. Biden will hold both of his first two major campaign stump speeches in Pennsylvania.

Joe Biden is finally out of the gate — and he's heading straight for the Keystone State.

Other Democratic candidates have already made moves in the state. Former Texas congressman and Senate candidate Beto O'Rourke visited Pennsylvania last month, and Sen. Bernie Sanders, I-Vt., who is running in 2020 as a Democrat, held a Fox News town hall in Bethlehem earlier in April.

"Democrats and Republicans know that the road to the White House runs through Pennsylvania, so every Democratic presidential candidate will be wise to focus their efforts here," Pennsylvania Democratic Party spokesman Brandon Cwalina said in a statement to CNBC.

The same day he announced his campaign, Biden traveled toward Pennsylvania, stopping in Delaware before a fundraiser headed by Sen. Bob Casey, D-Penn., and former Gov. Ed Rendell, D-Penn. That fundraiser is reportedly being held at the home of Comcast senior executive vice president David Cohen. Comcast is the parent company of NBC News.

Biden will hold his first major campaign event Monday in Pittsburgh, where he is expected to speak about rebuilding an inclusive middle class, according to NBC. Then on May 18, the former vice president will hold a rally in Philadelphia, where he will hash out his vision for closing the divides that are driving Americans apart.

Between those two dates, Biden will travel to Iowa, New Hampshire, California, Nevada and South Carolina — key states in the Democratic primary. But Biden appears to be taking early steps to lock down Pennsylvania, which holds 20 votes in the electoral college and where he already has some advantages over his opponents.

Biden spent the first decade of his life in Scranton, Pennsylvania, before his family moved to Delaware, the neighboring state where he would eventually serve six terms as a U.S. senator. Philadelphia was one of Biden's most important media markets during his decades in the Senate, according to Republican political strategist Ray Zaborney.

"He's uniquely built, if you will, for Pennsylvania," Zaborney told CNBC.

Even before he made his White House bid official, Biden was by far the top Democratic pick for Pennsylvanians, according to a recent Morning Call/Muhlenberg College poll of registered Democratic voters. Of the 405 registered voters who responded in mid-April, 28% said they would choose Biden in the Democratic primary. Sanders came in second with 16%.

Trump's last visit to the state was in October, when he and first lady Melania Trump came to support the victims of a shooting at a Pittsburgh synagogue. But Politico reported that senior advisors on Trump's 2020 team traveled to Harrisburg on Wednesday to meet with state GOP officials amid concerns about whether Trump can win in Pennsylvania in the next election.

Biden's campaign did not immediately comment about his strategy in Pennsylvania.

Republican National Committee Chairwoman Ronna McDaniel may have hinted at the GOP's own strategy for countering Biden and other Democrats' efforts to shore up support in Pennsylvania. Trump's razor-thin, roughly 44,000-vote victory in the Keystone State helped him to secure the White House.

"Biden chose Pennsylvania to launch his campaign — a state where the unemployment rate just dropped to the lowest level ever recorded," McDaniel tweeted shortly following Biden's announcement.

McDaniel TWEET

Zaborney said that he expected Pennsylvania Republicans to follow McDaniel's lead, by touting strong economic numbers during Trump's first three years in office and contrasting Biden's record with the president's.

"Is Biden what people are willing to throw away a good economy for?" Republicans might argue, Zaborney said.

In statements Thursday, Republicans appeared to be doing just that.

"Joe Biden helped President Barack Obama oversee the worst economic recovery following a recession in this country's history," Pennsylvania Republican Party Chairman Val DiGiorgio said, before listing Obama-era policies often criticized by the GOP, including the Iran nuclear deal and Obamacare.

"Joe Biden's record offers nothing to Pennsylvanians and a Biden Presidency would return this country to some of its least promising days," DiGiorgio said.

The RNC said in a statement that "Pennsylvania's unemployment rate just hit a record low thanks to President Trump's leadership on policies like the Tax Cuts and Jobs Act."

"We will continue to contrast the roaring economy Pennsylvanians have enjoyed under the Trump Administration with the failed policies of the Obama/Biden era."

Democrats used Trump's policy priorities to turn the tide in the state last year. They flipped several U.S. House districts and held on to a Senate seat and the governor's office in large part by criticizing Trump's efforts to repeal the Affordable Care Act.

Pennsylvania holds its primary election on April 28, 2020 — more than two months after the Iowa caucuses, which kick off the presidential primary election season. The top candidates for either party have usually cemented their leads by that time, making the Pennsylvania primary day far less consequential than the day of the general election itself.

But Philadelphia-area Democratic campaign strategist Aren Platt told the Associated Press in March that "when you have a big field like this and it's possible to win early-voting states with 10, 12 or 15 percent, it really is open to everybody."