WASHINGTON – Senator Reid of Nevada won election as leader of the shrunken Democratic minority yesterday and said he stands ready to cooperate with Republicans or confront them as he deems necessary.

“I always would rather dance than fight. But I know how to fight,” he said at a news conference after the Democratic rank and file chose him leader for the Congress that convenes in January.

Mr. Reid won his post as House Republicans, buoyed by election gains, tapped Rep. Dennis Hastert of Illinois for another term as speaker. Rep. Tom DeLay of Texas was re-elected majority leader, and the balance of the GOP leadership won new terms as well.

Mr. Reid, 64, said he and Democrats would stress expanded access to health care and increased support for education. “I believe in the minimum wage and we have to raise it,” he said.

Mr. Reid also cautioned majority Republicans not to “mess with the rules” in the Senate by trying to make it easier to override Democratic objections to some of President Bush’s judicial nominations.

He said the Senate had confirmed 203 of President Bush’s court nominations over the past four years and blocked 10. “I think they are crying wolf all too often,” he said of Republicans who used the 10 thwarted nominations to label Democrats as obstructionists.

Mr. Reid takes over a party with 44 seats in the new Congress, fewer than at any time since the Great Depression. He succeeds Senator Daschle, who was defeated for re-election on November 2 in South Dakota.

The 64-year-old Nevadan, who has long served as Mr. Daschle’s second-in-command, was elevated to leader in a closed-door meeting of Democrats who will serve in the Senate that convenes in January.

Senator Durbin of Illinois was unopposed to replace Mr. Reid as the party’s whip, the Democrat’s second-ranking Senate leader.

Mr. Daschle has served as party leader since 1995, leading Democrats in periods in which they were in the minority, the majority, and then back again.

There were other reminders of the November 2 election as Democrats met in a historic room in the Capitol. Senator Kerry of Massachusetts participated in the session as he picked up his Senate duties two weeks after losing his bid for the White House.

Mr. Reid said Mr. Kerry won ovations from fellow Democrats several times during the closed-door meeting.

Mr. Reid has a soft-spoken demeanor, but he showed an unyielding side when asked a question he did not want to answer.

“Next question,” he said when asked about his relationship with Senator Chafee, a Rhode Island Republican who has openly flirted with switching parties. When the reporter persisted, Mr. Reid said again, “Next question.”

The Nevada lawmaker played an instrumental role in Vermont Senator Jeffords’ leaving the GOP to become an independent in 2001, a switch that gave Democrats the majority.

Mr. Reid was nominated for the party-leadership job by Senator Byrd of West Virginia, who served in the post in the 1970s and 1980s. Seconding the nomination was Senator Nelson of Nebraska, who occasionally vexed Mr. Daschle by crossing party lines.

With the exception of abortion rights and gun control, both of which he opposes, Mr. Reid’s recent voting record on major issues puts him in the mainstream of Senate Democrats.

A veteran of 22 years in Congress, Mr. Reid voted against President Bush’s tax cuts in 2001.