A couple of hours into Loretta Lynch's lengthy confirmation hearing to be attorney general on Wednesday, Senator John Cornyn boiled the whole thing down to a single question.

"You're not Eric Holder, are you?"

"No, I'm not, sir," Lynch replied, as the crowded Senate room broke out in laughter.

With that response, she probably clinched the job. Lynch is the first prominent nominee of President Obama's to be considered by the Republican Senate majority, and the biggest incentive conservative lawmakers have for approving her nomination is to get Holder out of the Justice Department. Republicans grilled Lynch on many issues Wednesday, most aggressively on the legality of Obama's executive action on immigration. But at times, the hearing sounded more like an airing of GOP grievances against Holder than a job interview for his replacement.

For most of his six years as attorney general, Holder has had a notoriously toxic relationship with Republicans. The GOP-led House voted to hold him in contempt in 2012 over the Justice Department's refusal to turn over documents related to the "Fast and Furious" gun-running operation, and in recent years Holder has had heated exchanges with Republican lawmakers while testifying on Capitol Hill.

Lynch, 55, has served as the U.S. attorney in Brooklyn for the last five years (her second stint at that post), and she benefits, in the eyes of Republicans, from her lack of a close friendship with the president. Holder, by contrast, vacations with the Obamas and has described himself as "the president's wingman." Lynch didn't dissociate herself from Holder, but she made sure to promise "a new and improved relationship" with Congress. "If confirmed as attorney general, I will be myself," she said. "I will be Loretta Lynch." Republicans in turn treated her with far more respect and deference than they have Holder, even as she politely, but firmly, rebuffed their attempts to get her to criticize the president's immigration policy. (She did break away from Obama on a couple issues and indicated she was far more strongly opposed to the legalization of marijuana than he was, for example.)

Of course, just about every nominee for attorney general pledges independence and swears they'll impartially enforce the law. Holder's relationship with Republicans didn't deteriorate until after the Senate confirmed him to his post in 2009. Lynch's vote won't be unanimous; an immigration hawk, Senator Jeff Sessions of Alabama, called her defense of the administration's policy "very troubling," and Senators Ted Cruz and David Vitter also seemed like "no" votes.

Still, the Republican leadership was already inclined to support Lynch, and nothing she said in the first several hours of her marathon testimony damaged her candidacy. "You're just knocking them out of the park," a proud fellow Brooklynite, Charles Schumer, gushed at one point. Yet when Senate Republicans vote to make her the nation's chief law enforcement officer in the coming weeks, it may not be as much about who she is, but who she's not.