WASHINGTON – So it turns out the Obama administration won't get a practice run. The first real court fight will be for the Supreme Court – no warm-ups on an obscure appellate bench for this White House.

That means no practice run for administration critics, either. And the stakes are huge for them, too, as the nomination of federal appeals court Judge Sonia Sotomayor moves to the Senate.

She would be the first Hispanic on the high court, and Texas Sen. John Cornyn, a key Republican leader and for years a GOP point man on judicial nominations, is already on thin ice with Hispanics.

Earlier this month, in his capacity as chairman of the party's Senate campaign committee, he broke with tradition by endorsing a candidate in the primary to replace retiring Sen. Mel Martinez of Florida, the party's only Hispanic in the Senate.

Cornyn went the "safe" route, endorsing Florida Gov. Charlie Crist, an Anglo – thus rejecting the state's House speaker, Marco Rubio, who is seen as a rising Hispanic star.

Many Hispanics had already become disillusioned with Cornyn after he jettisoned a relatively moderate approach to immigration reform and sided with more hard-line anti-immigrant forces a few years back.

Here in the East Room of the White House, special guests like the attorney general Eric Holder, the Rev. Al Sharpton (like Sotomayor, a New Yorker) and an assortment of the judge's friends and former law clerks, were beaming.

Cell phone cams were clicking.

Over at the GOP headquarters, so were the beads on the political abacus. How to obstruct without looking obstructionist?

Cornyn has already called for everyone to take a breath.

"It is imperative that my colleagues and members of the media do not pre-judge or pre-confirm Ms. Sotomayor…. She must prove her commitment to impartially deciding cases based on the law, rather than based on her own personal politics, feelings, and preferences," he said in a statement.

The instinct among Cornyn and fellow conservatives on the Judiciary Committee will be to hyperscrutinize the nominee, to pick apart each ruling she has penned or supported, to paint her as a judicial radical.

Their motives are well-honed: Innate skepticism about anyone this president would offer a lifetime seat on the Supreme Court. A knee-jerk, inside-the-Beltway, desire to weaken the administration by bloodying his nominees whenever possible, especially when the stakes are so high.

To the conservative ear, "empathy" – that vague but loaded term the president has used to describe his ideal nominee since his days as a candidate – is code for judicial activism.

So we can expect Cornyn – in those soothing, thoughtful, judgelike and grandfatherly tones that his more strident colleagues value when such fights erupt – to angle for advantage.

He may end up voting for Sotomayor's confirmation in the end, but probably not.

The real question is, when it comes to the nation's fastest-growing demographic, will he bloody himself and his party along the way?