After helping to engineer Hamilton County Commissioner Pat DeWine’s (R) defeat in a special House primary Tuesday, conservatives are now focusing attention on his father’s re-election next year — believing that Sen. Mike DeWine’s (R-Ohio) participation in the deal on judicial nominees has left him vulnerable to a primary challenge in 2006.

Social conservatives are incensed at the elder DeWine, and their contempt for the Senator is one of the factors that ultimately contributed to the implosion of Pat DeWine’s bid to win the GOP nod in Tuesday’s special election.

Initially considered the frontrunner in the contest to succeed former Rep. Rob Portman (R-Ohio), Pat DeWine won just 5,455 votes out of a total 45,390 cast (14 percent). Former state Sen. Jean Schmidt was the top Republican vote getter and she is heavily favored to win the seat over attorney Paul Hackett (D) in the Aug. 2 special election.

The younger DeWine’s high-profile defeat has bolstered the hope of some conservatives that the two-term Senator will see a top tier primary challenge when he faces voters next year — even though there are no prospective candidates currently on the horizon.

Tony Perkins, president of the Family Research Council, said he believes that Pat DeWine was hurt by his father’s decision to be part of the compromise that thwarted Senate Majority Leader Bill Frist’s (R-Tenn.) goal to eliminate the judicial filibuster.

The FRC and other socially conservative organizations were vocal supporters of Frist’s proposal to change the Senate rules, seeing it as an opportunity to make it easier for like-minded nominees to be confirmed to the federal bench.

Perkins’ organization funded a radio campaign in Ohio following the compromise that targeted Sen. DeWine for his involvement. Perkins said he isn’t sure if the ads had a direct effect on Pat DeWine’s campaign, but added that a message was clearly delivered Tuesday to incumbents.

“I would certainly say it sends a signal,” Perkins said. “It is a wake up call for those who think they can compromise in this city and go home to campaign and not have repercussions.”

Perkins said FRC plans to continue its educational and voter registration activities in Ohio through the 2006 campaign and will work with other organizations to promote a conservative agenda.

Still, Perkins was careful not to say he wants DeWine defeated but made clear his group would prefer a more reliably conservative Senator.

“I wouldn’t say that I would like to see the defeat of Mr. DeWine,” he said. “I would like to see a strong conservative in the Senate, who will stand on the issue of marriage. He went against the marriage amendment in Ohio last year and then he got involved in this deal on the judges.”

In an e-mail to supporters Wednesday, Perkins used the Ohio special election as an example of the broader implications the judicial compromise could have.

“More politicians should take notice of conservative Christians throughout the country becoming more involved politically,” he wrote. “Conservative Christians traditionally support people, not parties, and they recognize that when it comes to core principles — there is no compromise.”

DeWine allies and many in the GOP establishment laugh at the idea that the Senator could be vulnerable from a challenge within his own party and at the notion that the judicial compromise has created any sort of opening for a competitive primary.

“Voters base their decisions on somebody’s entire record after they’ve had a chance to examine that record during a campaign,” DeWine spokesman Mike Dawson said. “During the course of six years there’s things that people are going to agree with you on and disagree with you on.”

As it stands now DeWine has no obvious primary challenger in sight, although some observers say his son’s defeat could make the race more attractive to potential opponents.

“Somebody might come out of the woodwork as a result of this,” noted one Republican strategist.

Secretary of State Ken Blackwell (R) would be the most formidable primary opponent, but he is firmly planted in the open-seat gubernatorial contest also slated for next year.

Former Rep. John Kasich’s (R-Ohio) name has been floated by some, but a source close to the one-time Budget Committee chairman said that Kasich had absolutely no interest in challenging DeWine.

While social conservatives are most upset by DeWine’s recent actions, other conservative groups are less likely to agitate for a primary challenge.

Club for Growth Executive Director David Keating said in an interview Wednesday that the anti-tax group is more focused on targeting moderate GOP Sens. Lincoln Chafee (R.I.) and Olympia Snowe (Maine) in 2006 because of their record on fiscal issues, than trying to defeat DeWine, who supported President Bush’s tax cut proposals. Still he held the door open to getting involved in Ohio if a top tier candidate emerged.

“DeWine’s record hasn’t been like Arlen Specter’s,” Keating said, referring to the senior Pennsylvania Republican who narrowly survived a 2004 primary in which the Club for Growth played a prominent role. “That’s not to say that if some really outstanding candidate came along that we wouldn’t take a serious look, because we might. Because DeWine’s record hasn’t really been that great on spending issues.”

While the impact of the judges’ compromise on Sen. DeWine’s statewide popularity remains unknown, there is some anecdotal evidence to suggest he has cause for concern.

According to Republican polling conducted in the 2nd district contest and obtained by Roll Call, the Senator’s favorability among the district’s party faithful fell dramatically in the last month.

DeWine had a 52 percent/10 percent favorable/unfavorable rating among likely 2nd district GOP primary voters, according to a survey taken May 10.

Subsequent polling conducted in early June showed that DeWine’s favorability had plummeted to 28 favorable/38 unfavorable in the wake of the judicial compromise.

“Mike DeWine took a very serious hit,” said one source familiar with the polls.

Meanwhile, Democrats say that DeWine is vulnerable next November as well.

Democratic Senatorial Campaign Committee Spokesman Phil Singer argued that DeWine’s support back home remains shallow and that the Senator’s “quest to be all things to all people” will complicate his re-election effort next year.

“DeWine has opted for political expedience time and time again and it’s finally catching up to him because he’s alienated his political base,” Singer said.

After heavily courting Rep. Ted Strickland (D-Ohio), who opted for a gubernatorial bid instead, Democrats currently have no announced candidates in the race. But they remain confident that one will emerge.

“We’re going to have a top tier candidate in Ohio,” Singer vowed.

Republicans, meanwhile, argue that DeWine’s participation in the judicial compromise will actually help him win Independent and Democratic-leaning general election voters in a swing state like Ohio.

“It helps Mike in the general tremendously because he’s seen as an independent,” said a source close to the DeWine camp.

Meanwhile, Pat DeWine’s fourth place finish in Tuesday’s primary was attributed to a mix of factors — all of which combined to drive his negatives to a point where he became no longer viable.

The same survey that showed Mike DeWine’s unfavorables had skyrocketed, showed that 43 percent of those surveyed said they had an unfavorable view of his son compared to 18 percent who said they had a favorable impression.

“The guy became hated,” said the source familiar with the poll. “It was a combination of both the infidelity issue, that was a big driver, and the judges was also a driver. They sort of came together in a poisonous cocktail for Mr. DeWine.”

In the end, Schmidt won with 31 percent of the vote, despite heavy attacks from the Club for Growth on radio and TV.

Former Rep. Bob McEwen (R), attempting a political comeback after 12 years out of office, came in second with 25 percent of the vote. He also finished second to Portman in a 1993 special election. Mark Preston contributed to this report.