Rep. Bob Inglis of South Carolina is, by most standards, a reliable Republican vote in Congress, politically cemented in the middle of his caucus.

During the first seven months of the 111th Congress, he has joined with fellow Republicans on 96 percent of House votes that pit most Republicans against most Democrats. When President Barack Obama has indicated a clear position on legislation, Inglis has supported that view just 27 percent of the time — even less often than House Minority Whip Eric Cantor of Virginia (35 percent), who is generally considered to carry impeccable conservative credentials.

But the 2010 election will test whether Inglis’ strongly Republican-leaning constituency in the South Carolina’s 4th District believes he is conservative enough. That’s because the six-term congressman has drawn four Republican primary challengers who argue that he isn’t.

Republican State Sen. David Thomas, when he launched his primary campaign in June, said he was “disappointed” in Inglis for voting in early 2007 against the buildup of U.S. troops in the Iraq conflict — a policy, instituted by President George W. Bush , known as the “troop surge” — and for voting in late 2008 for the financial industry assistance, or “bailout,” measure (PL 110-343).

Candidate Christina Jeffrey, a professor at Wofford College in Spartanburg, said in a statement on her Web site that Inglis is “symbolic of the path many Republicans have taken over the past few years as he has continued to compromise our conservative values.”

Other candidates include Trey Gowdy, a prosecutor, and Jim Lee, an information technology and business consultant. Gowdy, on his Web site, said there is a “near total disconnect between Washington and the people of the 4th Congressional District,” while Lee derided Inglis as a man who has “lost his focus and is now part of the system he originally went to Washington to change.”

Gowdy and Thomas, by virtue of their status as elected officials, start out with an advantage in name recognition, according to local political analysts. Gowdy also got a bit of a fundraising start over fellow challengers, though none had a big pile of money at mid-year. According to the candidates’ Federal Election Commission (FEC) filings, Gowdy raised about $88,000 and had $83,000 in cash on hand, followed by Jeffrey with $25,000 in receipts and $20,000 cash on hand, and Thomas with $17,000 in receipts and $12,000 cash. Lee did not report any contributions, confirming to the Greenville News in mid-July that he’d raised less than the $5,000 threshold that requires candidates to file FEC reports.

But the opponent field doesn’t have a big early catch-up chore, as Inglis has not done the kind of aggressive fundraising typical of incumbents trying to inoculate themselves from serious challenges. Inglis raised a modest $130,000 in the year’s first half, and with some leftover funds from his last campaign reported $180,000 cash on hand. Inglis is not, in fact, one of Congress’ champion fundraisers: In winning re-election in 2008 with 60 percent of the vote against a typically under-funded Democratic opponent, Inglis spent less than $500,000, by far the lowest figure for any of South Carolina’s six House incumbents.