SPRINGFIELD - From an emergency room doctor to a retired clown, candidates for the 2006 election are living by the axiom that if you don't succeed, try, try again.

Take Democrat David Gill of Clinton as an example.

Gill, an emergency room doctor from Clinton, has filed to run for a second time against incumbent Republican U.S. Rep. Tim Johnson of Urbana.

Gill said what he learned on the campaign trail in 2004 will help him cruise to victory two years after being defeated by a an almost 2-1 margin.

"It was a very steep learning curve," Gill said after the filing period closed Dec. 19. "But we created a lot of name recognition, which will help us get the word out and raise money."

The poster child for repeat candidates is U.S. Rep. Melissa Bean of Barrington who, in 2004, narrowly beat long-time incumbent Phil Crane in Illinois' 8th Congressional District.

Bean ran a respectable race in 2002 and, in her successful bid two years ago, was able to squeeze past the Republican in a district that had begun to lean toward Democrats.

Individuals who run and lose often, however, sometimes get stuck with the dreaded "perennial candidate" tag.

University of Illinois-Springfield political scientist Chris Mooney said candidates generally can lose twice before they begin losing support, which translates into less money and, usually, another loss.

"Once you've got the image of a loser, it's hard to shake," said Mooney. "If people think a candidate is going to lose, they don't give them any money."

Among those qualifying for the perennial tag this year are Ray Wardingley, Mark Frederickson, Robert Dallas and Anthony Williams.

Wardingley has run for Congress three times and also challenged Chicago Mayor Richard Daley in 1989. In 2002, he ran in Chicago's 1st Congressional District against incumbent Democrat U.S. Rep. Bobby Rush. This time Wardingley, a retired clown, is running in the 3rd Congressional District, which is represented by U.S. Rep. Dan Lipinski of Chicago.

Dallas and Williams hope a party switch will help their chances. Both ran in 2004 for seats in Congress representing parts of Chicago. They are back this year, but Dallas has filed to run as a Democrat after running as a Republican two years ago. Williams has switched from the Democratic Party to the Libertarian Party.

In downstate Illinois, there are a number of repeat challengers.

Democrat Steve Waterworth of Easton is again seeking to represent the 18th Congressional District.

Standing in his way is incumbent Republican U.S. Rep. Ray LaHood of Peoria, who beat him by a two-to-one margin in 2004.

Republicans are again targeting Rock Island Democrat Lane Evans, who has routinely fended off challengers in the state's 17th Congressional District.

Back again for another run at Evans is former television anchorwoman Andrea Zinga, who watched as 62 percent of the voters went with Evans in the 2004 general election.

This time around, Zinga faces a primary fight against Brian Gilliland of Aledo and Jim Mowen of Rock Island.

Voters in the 19th Congressional District, which runs from Springfield to the state's southern tip, will again see the name "Vic Roberts" on their ballots. The retired coal miner ran against incumbent Republican U.S. Rep. John Shimkus of Collinsville in 2002.