WASHINGTON – The ranks of Senate Republicans have thinned, and the team will go through a challenging, even painful rebuilding phase next year. Sen. John Cornyn may try to lead that effort.

Assuming he wins a second term – something the Democrats and their nominee, state Rep. Rick Noriega, hope to avert, naturally – the Texas Republican is eyeing a run for chairman of the GOP's Senate campaign arm.

"I'm interested in making sure that we're successful in re-electing a majority of Republicans in 2010 if we can't do it in 2008," the senator told Texas reporters the other day during his weekly conference call. "But I'm really not focused on that job at this point, because frankly, I've got more immediate concerns like getting re-elected."

Chairing the National Republican Senatorial Committee is a thankless job – raising as much money as possible, recruiting candidates, making sometimes-tough choices in parceling out the limited resources. Nevada Sen. John Ensign will give it up after the fall elections, and he isn't sugarcoating the challenge his successor will face.

"Cornyn would do a fabulous job. Norm Coleman's also talked about it [and] he'd do a fabulous job. Either one of them would be fantastic," Mr. Ensign said, referring to the only other senator expressing interest, a Minnesota Republican who's likely to face Al Franken, the ex-Saturday Night Live comedian, in November.

A good night Nov. 4 would cost the GOP only four Senate seats, Mr. Ensign said over lunch with reporters. "It would be a great night if we lost three seats."

Regaining the majority? That, he said, would be "fairly miraculous. ... I've told every Republican, whether it's John Cornyn, or Pat Roberts , or Jeff Sessions or Saxby Chambliss or any of them – if you have an R in front of your name this year, you better run scared. You better raise all the money you can raise."

Given the worst GOP environment since Watergate, Mr. Ensign is aiming to hang on to 45 Republican seats, a few more than needed to sustain a filibuster and provide a "firewall" against Democratic proposals.

He expects Mr. Cornyn to win "handily," and the Texas seat doesn't crack his top 10 list of worries.

Mr. Cornyn echoed the general assessment of the GOP's prospects. "We're all expecting this year to be a challenging year," he said.

Don't look for any Obama-McCain joint appearance at the LBJ presidential library in Austin next month.

So far, Barack Obama has brushed off an invitation issued Thursday from Lynda Johnson Robb and Luci Baines Johnson, and a similar invite from Nancy Reagan for an event at the Ronald Reagan library in Simi Valley, Calif.

"My father would be proud of this opportunity for Americans to embrace a Scripture verse he quoted often, 'Come, now, let us reason together.' " Ms. Robb said.

Sen. John McCain accepted both invites. In his quest to maximize the number of joint appearances, he's pushed for 10 town hall meetings, one each Thursday through late August. Mr. Obama countered Friday by proposing just one, plus the three debates planned for the fall by a bipartisan commission as well as an in-depth debate on foreign policy.

The McCain camp is basically calling the Democrat a chicken, but Obama spokesman Josh Earnest shrugged off the taunts and said it's still possible Austin will play host if they come to terms.

"I don't understand why proposing five debates in less than five months would leave anybody with the impression that this is something that we're shying away from," he said.