Shortly after 7 p.m. last night, actor Hugh Grant, looking dapper and nervous, slipped past a red velvet rope at Christie's International and up to a private skybox. The actor's turquoise-blue Liz, a huge 1963 portrait of actress Elizabeth Taylor by Andy Warhol, was on the block—and it wasn't cheap. Mr. Grant bought it at auction a scant six years ago for $3.6 million. Christie's now had it estimated at $25 million to $35 million and art-market players were widely viewing it as a barometer of the art market's long-unstoppable climb.

After it sold, Mr. Grant and a smiling entourage headed out. Whether the winning bid—$21 million, with Christie's commission bringing it to $23.5 million—was a disappointment or a triumph is in the eye of the beholder. It was emblematic of a suspenseful evening that brought in strong prices for post-war and contemporary art but, in the case of some "superstar" paintings, still fell short of what the auction house had expected.

All told, Christie's raised a robust $325 million, with nearly every artwork (93 percent, or 62 of 67 on the block) selling. These results tabled—at least in the near-term—concerns of an art-market collapse. Last night’s total kicked the amount of money spent publicly at New York art auctions in just the past week to more than $1 billion.

"There was palpable relief," said Sausalito, California, private art dealer Richard Polsky, author of the book I Bought Andy Warhol. A lot was at stake for the art industry: Normally after the twice-yearly major auctions, art dealers adjust prices. For the past few years, the direction has been unrelentingly up—until a major Sotheby's sale last Wednesday, where a fourth of the Impressionist and modern artworks didn't sell. As a result of last evening’s sale however, it looks like contemporary art dealers can largely keep steady at last spring's prices, said Mr. Polsky, at least until next spring’s blockbuster sales. (Sotheby's has its contemporary art sale tonight.)

As the evening began, a restlessness marked the packed-to-capacity auction. With not a seat open, even in the overflow gallery, a group of art dealers, collectors, and scenesters clad in black nervously circled Christie’s second-floor atrium like a long, dark centipede. But the mood lightened and all the pacing stopped as artwork after artwork swiftly found buyers.

Auctioneer Christopher Burge, noting that the first six items offered for sale set price records, dubbed the sale "rip-roaring." In the fiercest and longest bidding war of the evening, British diamond dealer Laurence Graff, a noted Warhol collector with his own version of Liz, vied back and forth for minutes—and millions—with a telephone bidder over Warhol’s bloodred portrait of Muhammad Ali (once owned by the Ali family). He lost; it eventually brought $9.2 million, about triple its presale estimate.

More typical was the reception for a powerhouse Gerhard Richter: Several bidders chased his giant 1963 Jet Fighter—but its record price of $11.2 million was still just a bit above its $10 million low estimate. Similarly, Jeff Koons' gleaming giant steel Diamond (Blue) sold for $11.8 million; New York art dealer Larry Gagosian was the winner. The price set a record for the artist, more than doubling his previous record, but it had been expected to rise as high as $20 million. The arguably “soft” price for the art star creates considerable interest over how Koons’ similarly priced giant acid-pink steel sculpture Hanging Heart will fare at Sotheby’s this evening.

The top seller at Christie’s was a large abstract Mark Rothko, Untitled (Red, Blue, Orange), 1955, which brought $34.2 million against an estimate of $25 million to $30 million. A record of $19.4 million was also set for artist Lucien Freud’s 1992 Ib and her Husband, which has hung in the Tate Modern museum.