PHILADELPHIA (AP) Former Pennsylvania congressman Joe Sestak began a 422-mile walk across the state Wednesday to kick off his campaign to capture the U.S. Senate seat occupied by Republican Pat Toomey.

Sestak announced his candidacy for the 2016 election outside Philadelphia's Independence Hall. He called for more government accountability and decried the "trust deficit" between politicians and the people who elect them."I want to earn, starting today, step by step, walking in the shoes of we Pennsylvanians, the trust of our people," Sestak said. "So join me. Walk with me."The casually dressed Democrat then changed out of a pair of high-top Reeboks and put on military-issued boots to walk with veterans and other supporters to the city's Vietnam Veterans Memorial a few blocks away.Sestak, a former Navy vice admiral from suburban Philadelphia, has set up a potential rematch with Toomey. He narrowly lost to Toomey, a former investment banker and congressman, in 2010.Toomey campaign strategist Mark Harris said Wednesday that Sestak has been pursuing the Senate seat ever since."While former congressman Sestak remains obsessed with his personal ambition for higher political office, Sen. Toomey will continue to keep his focus on ensuring Pennsylvanians' safety and security, and promoting fiscal responsibility in Washington," Harris said in a statement.Using the slogan "Joe Sestak is walking in your shoes," the 63-year-old candidate plans to walk with a different group each day including veterans, senior citizens and small-business owners until he reaches the western border of the state. Staffers said the effort would likely take until the end of the month.Sestak's 31-year Navy career included commanding an aircraft carrier battle group in Afghanistan and Iraq following the 9/11 terrorist attacks. After retiring, he was elected twice to the U.S. House of Representatives before pursuing the Senate post in 2010.Sestak notched a shocking primary upset against five-term Sen. Arlen Specter to win the party's nomination and square off against the conservative Toomey. Sestak lost the general election by 2 percentage points.He went on to teach public policy at Carnegie Mellon University in Pittsburgh. As the 2013-14 recipient of the General Omar N. Bradley Chair in Strategic Leadership, Sestak also taught at Dickinson College, the U.S. Army War College and Penn State University's schools of law and international affairs. All are based in Carlisle.Sestak flirted with a gubernatorial candidacy in 2013, but ultimately decided to pursue the Senate again.The campaign organization Friends of Joe Sestak ended last year with about $1.5 million in cash on hand, compared with $5.8 million for Friends of Pat Toomey, according to federal campaign filings.