An independent running in Illinois' 13th congressional district could garner substantial support in November. However, the candidate's Democratic opponent is now trying to keep him off the ballot.

David Gill is a Bloomington physician and ran for Congress four times as a Democrat. This year, however, he decided to run as an independent.

Gill criticizes both parties as controlled by "corporate interests" in a manner resembling Democratic presidential candidate Bernie Sanders. Now, members of his former party have filed an objection to prevent him from appearing on the ballot in November.

Democratic candidate Mark Wicklund is a long-time party activist and ran unopposed in the March primary. He personally filed his objection against Gill hours ahead of the deadline last week, calling the independent's run an "ego trip." He noted that it would be different if Gill was still with the party.

"If he was going to run again as a Democrat, we'd get behind you one more time," Wicklund said.

His main focus is challenging Gill's petition signatures, primarily by:

"[E]liminating the number of blank lines on his petitions and throwing off the signatures that are from out of the district."

Gill says his campaign acquired many more signatures than necessary. However, signatures from outside the district is plausible due to Illinois' gerrymandered map.

Starting east of the St. Louis area, the Illinois 13th congressional district extends to the northeast to Urbana. Additional metropolitan areas include Springfield, Decatur, and Bloomington. Each of the major cities in the 13th also border other districts. Gill had to obtain nearly 11,000 valid signatures to qualify for the ballot. As a major party candidate, Wicklund needed fewer than 750.

Although an independent, Gill has significant name recognition due to his previous campaigns. Running as a Democrat in 2012, Gill lost to current-Rep. Rodney Davis by barely 1,000 votes.

Wicklund's legal action also follows an accusation against his own party. According to Wicklund, U.S. Rep. Bill Foster, a Chicago-area Democrat, is trying to force him from the ballot. Foster's presumption is that Gill is a stronger general election candidate who could appeal to Bernie Sanders' supporters. According to Wicklund, Foster threatened to cut off party donations if Wicklund remained on the ballot.

On the prospect of replacing Wicklund for the Democrats, Gill has only said, "I would give it some thought."

The University of Virginia Center for Politics rates Illinois' 13th congressional district as "Safe Republican." The wrangling over the Democratic ballot could be rendered moot, but voter turnout is often higher in presidential elections and can alter expectations for all the candidates.

Image: Independent congressional candidate David Gill