Perdue fared poorly in this year's governor's race. He finished fourth in a six-way race, trailing Gov. Earl Ray Tomblin, House Speaker Rick Thompson and Secretary of State Natalie Tennant. Perdue even lost his native Boone County.
During the race, some voters apparently soured on Perdue, who was the first of the Democrats to run negative TV ads about his opponents.
In the third week of April, 32 percent of voters had a favorable impression of Perdue, while 26 percent had an unfavorable opinion of him, according to a poll with a 5.9 percent margin of error conducted by Democratic pollster Public Policy Polling.
But those numbers basically flipped in a poll by the same firm just days before the May 14 primary. In that poll, with a 3.6 percent margin of error, 24 percent of voters said they had a favorable impression of Perdue, while 31 percent said they did not.
Nelson is still serving his first term in the House but has a history in the banking industry.
Nelson didn't directly mention the federal probe but said, "With any public service, we always must keep an arms-length transaction between personal activities and public activities."
Nelson said he started his career at United Virginia Bank, which is now Suntrust. He eventually worked as a corporate loan officer and investor for the bank.
He joined City National as its chief financial officer in the early-1990s and oversaw commercial lending and the bank's investment portfolio.
In about 2000 he co-founded Mountaineer Capital, a venture capital firm that invested in small businesses in West Virginia and the surrounding area. He left there about four years ago to devote time to his parents, who had health issues. Since then he's been investing in oil and gas and real estate.
Nelson said he expects to make a decision by the end of the year, possibly within the next two weeks.
"I'm still talking to people, both in and outside of government, and part of this also is, 'What is the top-down ticket for the party next year?'" Nelson said. "I think it's very important to have a solid ticket, top to bottom."
Republican Bill Maloney, who lost to Tomblin in the general election by less than 3 percent, has filed papers to begin raising money for a 2012 bid. There are also announced Republican candidates for Supreme Court and agriculture commissioner, with additional but unconfirmed rumors about candidates who could run for attorney general or secretary of state.