In just nine months Karenna Gore and Andrew Schiff went from how-do-you-do to I-do; from an informal date in October to Aretha Franklin serenading the newlyweds under a massive white tent Saturday night.

After the wedding ceremony at the Washington National Cathedral came a party at Mom and Dad's -- the vice presidential mansion. Franklin sang "The Way I Love You" for the bride and groom's first dance -- and later performed a rockin' set. Grammy-winning fiddler Mark O'Connor played "Tennessee Waltz" for Karenna's second dance, with her father.

When bandleader Gene Donati called for the family to join them, sister Sarah Gore, 18, turned to President Clinton and asked, "Wanna dance?" Yes, he did. And so did nearly all of the 300 guests, who arrived shortly after 7 p.m. and left around 12:30 a.m. when the bridal couple vanished into their limo.

Their 6 p.m. wedding merged the Gores of Tennessee and the Schiffs of New York. The political clan claims three former senators, one of whom is father of the bride -- Vice President Al Gore. The Schiffs' 19th-century patriarch was Jacob Schiff, the powerful banker and philanthropist. Some of his descendants, including father of the groom David Schiff, are still in high finance.

Several invitees called it the best wedding they'd seen. "After the ceremony, Drew and Karenna came up the aisle, then Tipper and Al Gore, then his father, Albert Gore Sr., who yelled God Bless America.' Everybody clapped," said a guest.

Karenna wore the simplest of extravagant wedding gowns, an ivory satin Vera Wang with a fitted, sleeveless bodice, full skirt and train. The groom wore a tux and a big grin.

The pair was introduced in October by Chris Downey, wife of former New York representative Tom Downey. In November, Drew joined Karenna in Little Rock for the Clinton-Gore victory bash. And by mid-March they were engaged, said Georgetown University's president, the Rev. Leo J. O'Donovan, who's known the groom for more than a decade.

Might Karenna, a Harvard grad who worked for a TV station in Spain and for Microsoft's cybermag Slate in Seattle, be too young to wed at 23?

"It's young for today, relatively speaking," O'Donovan told The Source, but she's been out in the world and is "a very thoughtful young woman."

Given the two families' Rolodexes, the guest list could easily have mushroomed. But Karenna insisted on family and close friends. Period.

Security was understandably tight, with Secret Service agents and cathedral guards all over the grounds. Moments before the ceremony ended, however, one gate crasher came perilously close to slipping in the door through which the newlyweds would soon emerge.

But the hapless raccoon was quickly shooed away.

Among those who did get in: Housing Secretary Andrew Cuomo and Kerry Kennedy Cuomo, Agriculture Secretary Dan Glickman and wife Rhoda, Sens. Barbara Mikulski and Joe Lieberman, Reps. John Lewis and Tom Lantos, Slate editor Michael Kinsley, cosmetics mogul Leonard Lauder and wife Evelyn, and former HEW secretary Joe Califano, for whom the groom worked on substance abuse issues. And, of course, the Downeys. These days Drew Schiff, 31, is a New York Hospital primary care physician; Karenna starts law school at Columbia University in September. It is unclear how much entertaining they will do once classes begin. But judging by their Tiffany wish list, they eventually anticipate a gracious social life.

They've gotten lots of $22 mugs, some $50 champagne flutes and $95 highball glasses, a $700 decorative flower pot and an $800 coffee pot. But as of Saturday, no one had bought them the sterling silver Elsa Peretti platter ($3,500) or soup tureen ($5,000) they requested. In between pre-wedding fittings and parties and chats with caterers and florists, Karenna has managed to write a number of thank-you notes. And on Thursday, she slipped out to Restaurant Nora in Dupont Circle for her last just-the-two-of-them dinner with Dad as a single woman.

CAPTION: Karenna Gore and Andrew Schiff, hand-in-hand nine months after meeting.

CAPTION: Matchmaker Chris Downey and her husband, Tom.

CAPTION: One big, powerful family: The Schiffs, left, and the Gores leave the cathedral.