WASHINGTON (AP) _ Republicans can hardly contain their glee as they watch Barack Obama battle through a rocky period. And why should they?

Nothing else is breaking the GOP's way this year. But, at least now, the Democrats' political phenom is tarnished, and, if he defeats Hillary Rodham Clinton for the Democratic nomination, will enter the general election campaign not only bruised and battered — but also carrying baggage as he faces Republican John McCain.

"We've had a rough couple of weeks. I won't deny that," Obama said Friday.

The Illinois senator has repeatedly had to address — and repudiate — the ranting of his bombastic former pastor, the Rev. Jeremiah Wright. Obama has continued facing questions about his relationship with indicted Chicago businessman Antoin "Tony" Rezko. The candidate's patriotism has been questioned. So has his readiness.

On the eve of a critical Pennsylvania primary, Obama caught flak for claiming that small-town folks are bitter and thus cling to guns and religion. Then he turned in a lackluster debate performance. He ended up losing that primary to Clinton in part because he didn't attract enough white, working-class voters.

Now he finds himself in the midst of competitive contests in two more states. Losses Tuesday in Indiana and North Carolina would further weaken him. Even if he manages to hold off Clinton in those and the final primary contests, Obama would essentially limp to the nomination.

"The bark is stripped off him a little bit," said Reed Galen, a Republican who worked on President Bush's campaigns. "Are the folks on the Republican side of the aisle happy to let Hillary do that? Absolutely."

Among Republicans and Democrats alike, Obama's turbulent time is raising questions about why he can't seem to put away Clinton after a 16-month primary fight and whether Obama — in his first hard-fought race — is prepared not only to go up against McCain this fall but also to withstand the rigors of the White House.

Republicans hope Obama will be damaged goods come the general election and McCain will have a stronger shot at hanging onto the White House in an extraordinarily difficult political environment. Most Americans disapprove of Bush's job performance and think the country is on the wrong track, while the Iraq war continues and the economy bears down on — if it's not already in — a recession.

The GOP now sees a glimmer of light — a variety of Obama vulnerabilities they can try to exploit if he is the nominee.

One prominent Democrat who backs Clinton recognized as much.

Last week, Indiana Sen. Evan Bayh raised the possibility that the GOP will use Obama's association with Wright to try to destroy his character in a general election as the pro-Republican group Swift Boat Veterans for Truth did to Democrat John Kerry in 2004. Said Bayh: "I'm sure the far right will be out there trying to do the whole 'Swift Boat' thing."

Already, Republicans are testing a theory that Obama could be a liability for Democrats down-ballot, running ads in special congressional races that linked the Democratic candidate to Obama in hopes of helping the Republican candidate. It didn't work in Louisiana. The Democrat won Saturday.

Phil Musser, a Republican strategist who backed former Massachusetts Gov. Mitt Romney's GOP presidential bid, said of Obama's woes: "These are very damaging self-inflicted wounds and may heal over with a lot of happy talk at the Democratic convention, but may be re-exposed in the fall campaign."

Indeed, GOP operatives are intently watching the Democratic primary fight to see how to push Obama's buttons. They also hope Obama's missteps and losses have alienated key general election constituencies — or at least planted negative impressions with them that will last into the fall.