WASHINGTON — Challengers for congressional seats in St. Louis and across Missouri are trumpeting recent fundraising successes in a political season offering positive signs for outsiders.

But experts point out that even when challengers are flush with cash, incumbency can be priceless.

Propelled by potent anti-government sentiments that erupted over the summer, Ed Martin, a St. Louis Republican, was among several challengers in Missouri who raised more than $200,000 during a recent three-month reporting period, according to campaign finance reports filed with the Federal Election Commission.

Martin outdistanced Rep. Russ Carnahan, D-St. Louis, in filings that apparently didn't include a batch of Carnahan's proceeds from House Speaker Nancy Pelosi's visit to St. Louis Oct. 3 on his behalf. Carnahan reported $164,000 in contributions for the quarter.

"I think there's dissatisfaction out there, and it may be countrywide," Martin said.

Missouri Democratic Party spokesman Ryan Hobart

responded: "It's not much of a surprise that a lifelong political operative from the Republican Party would be able to raise money from his base."

Challenger successes in Missouri had a bipartisan flavor. Democrat Tommy Sowers, a lecturer at the Missouri University of Science and Technology in Rolla and a first-time candidate, also brought in more than $200,000, outpacing Rep. Jo Ann Emerson of Cape Girardeau, the incumbent Republican.

In winning her seventh term last year, Emerson polled 71 percent of the vote from her southeastern Missouri district — the second-highest Republican percentage in a congressional race in the state.

But Sowers, an Iraq war veteran, calculated that he raised more money in a quarter than all of Emerson's opponents have over the last 10 years.

"We've got a lot of supporters who, I think, are frustrated with the district and the region and see this as an opportunity to change that," he said.

With most recent polls showing that fewer than 1 in 4 voters approves of what Congress has been doing of late, challengers are tailoring outsider appeals.

"There's just a huge sentiment against lifetime career politicians," said Billy Long, a Republican auctioneer and real estate broker campaigning for the southwestern Missouri district opening with Rep. Roy Blunt's departure to run for the Senate.

"People are elated when they hear I'm not a politician and have never run for office before," added Long, who raised $104,000 last quarter and has $405,000 on hand.

Challengers cited the benefit of tapping donors at a time when voters are upset over government spending and concerned about the shape of the pending health insurance overhaul. But the landscape could be different in 13 months, experts note.

And with signs pointing to GOP successes in House races next year, Democrats nationally are girding for battle. Campaign reports show that the Democratic Congressional Campaign Committee outraised its GOP counterpart 2-1 in September, with $7 million in receipts.

"We have an environment where nonincumbents have a good argument to make — that Washington is still broke," said Stuart Rothenberg, a commentator in Washington. "But my guess — and I think it's a well-informed opinion — is that by the time we get to next year, the election will be a lot more about Barack Obama."

Rothenberg, who publishes a nonpartisan newsletter focusing on elections around the country, pointed to the difficulties unseating incumbents, who typically win re-election more than 90 percent of the time. Besides being well-known already and having a free means of communicating with people, most incumbents can rely on a ready-built flow of money from political action committees seeking influence and access.

The money disadvantage is a chief reason why most House members in the St. Louis area have drawn no opposition.

Rep. Ike Skelton, D-Lexington, is among the incumbents targeted by opponents who are raising money aggressively. But Skelton can take comfort in the balance of his own fund, thanks in large measure to PACs. He reported receipts of $332,000, about two-thirds from political action committees, and $600,650 in the bank.

Likewise, PACs provided nearly one-third of $347,000 in receipts during the quarter reported by Rep. Todd Akin, R-Town and Country. His challenger for the GOP nomination, Liz Lauber, of Kirkwood, reported $2,600.

Candice Nelson, of George Washington University, an expert on congressional elections, summed up the mission of challengers: "For an incumbent to be defeated, a challenger has to make two arguments: that the incumbent needs to be fired and that the challenger would be a better replacement."

Jacob Carpenter of the Post-Dispatch Washington Bureau contributed to this report.