Mike Parrish, a Malvern businessman and former Army aviator, on Tuesday said he is seeking the 2016 Democratic nomination for U.S. House in the Sixth District, citing a "fundamental lack of leadership" in Washington.

"Folks in Congress are focusing on their own personal interest and putting politics over the people's business," Parrish said in an interview. "I'm not a career politician. I have a fresh perspective."

In 2014, Parrish launched a campaign for the Chester County-based seat, but stepped aside in favor of physician Manan Trivedi, who had been the Democratic nominee twice before. Republican Ryan Costello, former chairman of the Chester County commissioners, won and is in his first term.

The seat was held for six terms by former Rep. Jim Gerlach (R.,Pa.), who had decided not to seek reelection. The district also includes portions of Montgomery, Berks and Lebanon counties.

Parrish, 51, said he wants to focus on making college more affordable; science, math and engineering education; and small business growth. He also is focused on the Veterans Administration, struggling with management problems.

"What's going on is a travesty," Parrish said.

He graduated from West Point in 1985 and spent 14 years in the Army as a helicopter pilot and operations officer, and is a veteran of the first Persian Gulf War. He also has a master's degree in aeronautical engineering from Stanford, and an MBA from the Wharton School at the University of Pennsylvania.

In civilian life, Parrish has been chief executive officer of several companies, and founded an environmental services firm before selling it. He also worked for General Electric.

Democrats see a chance to dislodge the freshman Costello before he gets entrenched as an incumbent, hoping that the higher turnout of a presidential election will help in a district that leans Republican.

Parrish is the first Democrat to announce for the seat, and the party's campaign committee likes his profile. If there is a Democratic primary, he could have to explain an issue that came up last year: Parrish was a Republican until he changed his registration in December 2013, and he has contributed money to former Gov. Tom Corbett in 2010, John McCain in 2008 and Mitt Romney in 2012.

"I'm very much a centrist moderate, and I realize the Republican Party is going farther to the right," he told The Inquirer last year. "It's no longer reflecting my values."

He called himself an environmentalist and said he respects women's rights, adding that the Democratic Party "is much more embracing to those ideas."

A primary seems possible. Joe Denham, an anesthesiologist at Children's Hospital of Philadelphia and a supervisor in West Whiteland Township, Chester County, is seriously considering seeking the Democratic nomination, a spokesman said.