After receiving Congressional nominations (Sen. Paul Sarbanes and Rep. Charles Mathias) to the U.S. Air Force Academy, Sheeler broke his wrist and was unable to attend. Instead, he paid his way through University of Maryland and the University of Illinois and later joined the Marine Corps having served as a combat officer (tanks and anti-armor), training officer and staff officer from 1982 to 1992 on active duty and reserves. Sheeler served as a staff officer during the Gulf War.
In 1992, Sheeler joined Allison Appraisals & Assessments, a nationwide business appraisal, advisory and litigation services firm. He filed for personal Chapter 7 bankruptcy in 2001 after accruing more than $190,000 in debt, mostly on credit cards. Sheeler has taken responsibility for his personal financial failing due to health problems and a divorce settlement, and said he considers this event an "asset" that gives him "additional sensitivity to folks who are one paycheck short of financial ruin and those who have overcome personal adversity." He has since repaid these balances excluding the sums owed by his past wife.
Sheeler received a Ph.D. with a concentration in Finance from the Union Institute and University in 2004. Sheeler has been an adjunct professor at Bryant University in Smithfield, Rhode Island of Finance, Business & Entrepreneurship.
According to Sheeler, the September 11 attacks inspired him to become involved in politics. While Sheeler was originally a Republican and supported some of Ronald Reagan's politics and actions while serving as California Governor and later as U.S. President, he felt that the party was not compassionate enough and switched to the Democratic Party.
In 2004, Sheeler made a late entry into the race to represent District 34 in the Rhode Island Senate, which includes parts of Charlestown, Exeter, Hopkinton, Richmond, and West Greenwich. As an independent candidate, Sheeler challenged Sen. Kevin A. Breene, a Republican whose family had lived in the town for generations and four-term incumbent. Sheeler lost the race, getting 41 percent of the vote against the incumbent, who said that Sheeler outspent him 4-to-1.
Sheeler ran for the Rhode Island U.S. Senate seat then held by Republican Lincoln Chafee. However, Sheeler was defeated in the Democratic primary by Sheldon Whitehouse on September 12, 2006. Sheeler finished third in the race, as he also trailed perennial candidate Christopher Young.
Sheeler ran on a platform opposing the Iraq War, promoting campaign and voting reform, and ending foreign oil dependence. He also called for replacing the death penalty with life imprisonment. He has publicly expressed the need to reverse President George W. Bush's tax cuts out of a belief that will reverse the national deficit and reliance on Asian loans. He called for the impeachment of President George W. Bush on a billboard along Route 95 in Providence.
Sheeler did not fare well in the polls, although some opinion pieces in March and April in The Providence Journal encouraged voters to consider Sheeler a legitimate candidate. Sheeler garnered 8 percent of the vote, compared with 10 percent for Young and 82 percent for Whitehouse.
After the primary, Sheeler took the unusual step of endorsing Chafee instead of Whitehouse.