Democratic strategists are bracing for losses in the 2010 midterm elections, but the party has shown early fundraising strength in some open House districts they hope to wrest from Republican control and while offsetting expected defeats elsewhere in the nation.

In GOP-held districts in Pennsylvania, Illinois and Delaware, Democrats have outpaced the Republican opposition through this year’s third quarter, according to an analysis of updated campaign finance reports recently filed with the Federal Election Commission.

Based on the reports, the top fundraiser in an open-seat House race is Doug Pike (D), a wealthy former newspaper editorial writer who is seeking a Democratic-trending suburban and exurban Philadelphia district that Rep. Jim Gerlach (R) is giving up to run for governor.

Pike reported $238,000 in third-quarter receipts and has raised $903,000 overall, $622,000 of which came from his own pockets. Pike is the leading fundraiser in part because of his personal wealth and in part because he began running for Pennsylvania’s 6th back in April, three months before Gerlach announced his candidacy for governor.

Pike is vying for the Democratic nomination with Manan Trivedi, a physician and Iraq War veteran who reported raising $127,000 in the third quarter, about one-tenth of it from his own pockets.

The Republican primary also includes a self-funder — Steven Welch, a businessman who loaned his campaign $500,000 of his $559,000 in receipts. Welch is competing for the GOP nod with state Rep. Curt Schroder, who raised $109,000, and Ryan Costello, a county official who took in $31,000.

One of the nation’s most expensive 2010 races is playing out in Illinois’ 10th district, a collection of suburbs north of Chicago that Rep. Mark Kirk (R) is giving up to run for the Senate. Both parties are preparing for competitive primaries on Feb. 2, the earliest primary date in the nation.

The top fundraiser in Illinois’ 10th is state Rep. Julie Hamos (D), who reported raising $567,000 in a little more than two months as a candidate. Nearly all of those funds came from individual donors.

Hamos needs a large treasury to boost her name recognition in a primary in which her chief opponent is Democrat Dan Seals, a business consultant who is well-known to primary voters after waging competitive but losing campaigns to Kirk in 2006 and 2008. Seals reported raising $303,000 in the third quarter, all of it from individual donors.

The best-funded Republican is Dick Green, the founder of a stock market analysis service. Of his $304,000 in third-quarter receipts, 75 percent came from Green himself.

Bob Dold, a businessman, took in $258,000 for the quarter, most of it from individual donors. State Rep. Elizabeth Coulson, another leading contender for the GOP nomination, loaned her campaign $50,000 of her $178,000 in third-quarter receipts, which also included contributions from committees linked to Illinois GOP Reps. Aaron Schock, Timothy Johnson and John Shimkus and Oklahoma Rep. Tom Cole, a former chairman of the National Republican Congressional Committee.

Democrats also have the early fundraising start in Delaware’s at-large district, in which former Lt. Gov. John Carney (D) has been campaigning since April for the seat that Rep. Mike Castle (R) is leaving to run for Senate. Carney reported raising $165,000 in the third quarter and $427,000 overall. No Republican reported raising money during the reporting period because Castle announced his Senate candidacy in early October, after the end of the third quarter.

Democrats have talked about making a run at Florida’s 12th district, a mildly Republican area in the state’s midsection that Rep. Adam Putnam (R) is giving up to run for state agriculture commissioner. But Lori Edwards, a county elections official and the likely Democratic nominee, has lagged in early fundraising, taking in just $39,000 for the quarter and $141,000 for her campaign to date. Republican leaders prefer Dennis Ross, a former state legislator who took in $144,000 for the quarter and $381,000 overall.

Kansas’ Wichita-based 4th district is difficult political terrain for Democrats, though state Rep. Raj Goyle (D) took in $404,000 in his first quarter of fundraising — substantially more than any of the Republicans running. Rep. Todd Tiahrt (R) is running for the Senate.

The Republicans are making a major play for Pennsylvania’s 7th district, a collection of suburbs near Philadelphia that Rep. Joe Sestak (D) is leaving to run for the Senate. Pat Meehan (R), a former federal prosecutor, took in $212,000 after just two weeks as an active candidate. He nearly matched the total of state Rep. Bryan Lentz (D), who raised $220,000 after nearly two months as a candidate.

Most of the 18 open House seats are in districts that are so strongly Democratic or Republican that the key elections will be the primaries held months before noncompetitive general election races.

In Oklahoma’s 5th district, a Republican-leaning area in and around Oklahoma City that Rep. Mary Fallin (R) is giving up to run for governor, two Republican candidates have topped $400,000 in receipts ­­— state Rep. Mike Thompson ($420,000) and former state Rep. Kevin Calvey ($419,000). The Democrats don’t have an announced candidate in this district, which gave Sen. John McCain (R-Ariz.) 59 percent of the vote in the 2008 presidential election.

Republicans also seem assured of retaining Missouri’s southwestern 7th district, which Rep. Roy Blunt (R) is leaving open to run for Senate. Billy Long (R), an auctioneer, leads the candidate field with $452,000 in total receipts after raising $105,000 in the past three months.

In Alabama’s 7th district, a majority black and staunchly Democratic area in and around Birmingham, the leading money-raiser is lawyer Terri Sewell (D), who reported raising $105,000 for the quarter and $403,000 for her campaign to date.