A tea party favorite whose election to the Senate in 2010 marked his entry into electoral politics, Ron Johnson has displayed a genial demeanor that’s won friends on Capitol Hill even as he’s remained committed to the tough deficit-cutting talk that helped bring him to Washington.

During his first two and a half years in the Senate, the Wisconsin Republican has compiled an unabashedly conservative voting record, earning a perfect rating from the American Conservative Union.

An outspoken advocate of curbing spending and downsizing government, he dropped off the Senate Appropriations Committee after the 112th Congress, citing the panel’s “dysfunction.” But he has remained on the Budget Committee, where he can come off as an aggressive, detail-oriented interrogator during committee hearings.

In addition to retaining the allegiance of the tea party groups that backed his candidacy, Johnson has earned respect among his Senate colleagues.

Late in 2011, he narrowly lost a bid to Roy Blunt of Missouri for the No. 5 slot on the Senate GOP leadership team. Now he is serving as the numbers point man among a dozen GOP senators, including more senior colleagues, who are meeting with White House officials in private talks that could be the prelude to deficit reduction negotiations.

Johnson draws on his own experience when he talks about the free-market work ethic. Born and raised in Minnesota, he earned money as a kid by mowing lawns, shoveling snow and delivering newspapers. He lived at home and worked full time while attending the University of Minnesota, graduating debt free with $7,000 in the bank.

Employed first as an accountant and later as a machine operator, Johnson helped launch a plastics manufacturing firm, Pacur, with his brother-in-law, a business that made him wealthy.

Johnson used part of his wealth to fund his successful 2010 Senate campaign against Democratic Sen. Russ Feingold. In that first bid for office, he vowed to reduce federal spending and spur economic growth.