State Republicans are eager to break into Hawai'i's congressional delegation via the free-for-all for the 2nd District House seat being vacated by U.S. Rep. Ed Case.

They have a promising array of potential candidates led by Honolulu Prosecutor Peter Carlisle, Windward state Sen. Bob Hogue and former Honolulu Councilman Mike Gabbard, who lost to Case in 2004.

But even against a splintered field of Democrats, the odds are steeply against the GOP in this strongly Democratic district, which has never elected a Republican to Congress.

The numbers from the 2003 special election to replace the late U.S. Rep. Patsy Mink have to be daunting to Republicans.

State Rep. Barbara Marumoto, the top Republican in a race that featured more than 40 candidates but light voter turnout, finished a distant fourth to Case with less than 6 percent of the vote.

The top 10 Republican vote-getters combined received fewer than 16 percent of the votes, compared to 80 percent for Democrats Case, Matt Matsunaga and Colleen Hanabusa.

And these candidates were no slouches as Hawai'i Republicans go; seven of the 10 were current or former elected officials.

Republicans might argue that a better measure of the core GOP vote in the 2nd District is the 79,072 votes received by Gabbard against Case in 2004. But even that was only 36 percent of the vote, far short of the 133,317 votes received by Case.

The encouraging figure for the GOP is the large number of prominent Democrats looking at the House race, although the field could thin once party leaders and labor unions run their polls and weigh in.

For now, three have filed — state Sens. Gary Hooser and Ron Menor and state Rep. Brian Schatz — and at least a half-dozen more current and former officeholders have expressed some level of interest.

The best scenario for Republicans would be if a Democratic candidate emerges from a crowded primary with a small plurality — and bad feelings linger among supporters of the losers.

That could open the door for an upset by a moderate Republican with good name recognition and a broad enough appeal to reach across party lines.

The most likely to achieve this appear to be Carlisle or Hogue — both popular and proven vote-getters whose support has cut across demographic lines.

It would be a coup for the GOP to land Carlisle, who runs for prosecutor as an independent, and party leaders might not want to welcome him with a primary fight.

Hogue, who is up for re-election and would have to give up his current job to run for Congress, might be persuaded to stay put and preserve his previously Democratic Senate seat for the GOP.

Gabbard is being promoted for the Leeward state Senate seat held by Brian Kanno, who is shaping up as this year's Cal Kawamoto — the Democratic lawmaker who has most worn out his welcome with voters.

One keenly interested observer of the GOP maneuvering is Case, who is counting on a big Republican crossover vote to help him unseat U.S. Sen. Daniel Akaka in the Democratic primary.

If there's a lively race in the Republican congressional primary to keep GOP voters home, it could doom Case's already long-shot chances.

That would cause few tears among Republican leaders, who have no viable candidate of their own for the Senate.

Akaka, 81, would likely serve one more term at most, opening the seat for a possible future Republican takeover by a candidate such as Gov. Linda Lingle.

If Case wins at 53, he'd probably settle in for a long time and be difficult for any Republican to beat.

David Shapiro, a veteran Hawai'i journalist, can be reached by e-mail at dave@volcanicash.net.