WASHINGTON – A former presidential candidate, Governor Dean, is stepping up his lobbying effort to succeed Terence McAuliffe as chairman of the Democratic National Committee and is canvassing for support on Capitol Hill, House members said.

His focus has been on lawmakers who endorsed his White House bid, but the former Vermont governor is also lobbying members of Congress who backed Democratic primary rivals Rep. Dick Gephardt of Missouri and Senator Kerry. Dr. Dean has touted his success at grassroots politics and his fund-raising prowess as reasons why he should be elected to the post, arguing that he can lift the party out of the doldrums.

Dr. Dean’s push on Capitol Hill came as senior Democrats said President Clinton’s preference for national party chairman could prove significant. As yet Mr. Clinton has not signaled his pick, but those close to him reportedly prefer his secretary of labor, Alexis Herman.

Ms. Herman worked closely with Ron Brown, who was party chairman in the 1990s. Her supporters argue that coming from Alabama she is better able than Dr. Dean to understand what appeals to Southern voters.

As the behind-the-scenes lobbying heated up and moderate Democrats were sizing up their best chance of blocking Dr. Dean, the Senate minority leader, Harry Reid of Nevada, endorsed an idea first floated by the man he is replacing as the top Democrat in the upper chamber, Senator Daschle of South Dakota.

Mr. Daschle has argued that the Democrats should name two chairmen: one as the public face of the party and the other to concentrate on fund-raising and finance.

That proposal, if adopted, would boost the chances of Governor Vilsack of Iowa to secure the chairmanship. He would be unable to run the national committee on a day-to-day basis because of his official responsibilities in the Hawkeye State. The person Mr. Daschle has been touting as the other chairman is a Manhattan financier and cable-television executive, Leo Hindery Jr. A major Democratic fund-raiser, Mr. Hindery has met with Democratic lawmakers to discuss the option.

“One of the things that we talked about is to make sure there is somebody there on a day-to-day basis to handle things,” Mr. Reid, who supports Mr. Vilsack, said.

If co-chairmen are appointed it wouldn’t be the first time that the DNC has gone for that option. In 1995 Mr. Clinton named two party chairmen: Senator Dodd of Connecticut as general chairman and Donald Fowler as national chairman, to run the daily operations of the Democratic National Committee.

Mr. Vilsack, too, has been up on Capitol Hill canvassing lawmakers. But according to House aides, Dr. Dean at this stage appears better organized at working Capitol Hill.

He outdid his rivals in House endorsements on the campaign trail, gaining the official backing of 38 members. One of the lawmakers who backed Dr. Dean, Rep. Neil Abercrombie of Hawaii, told the Hill newspaper: “We need to keep the energy of our young people, and nobody would do that better than Howard Dean. It’s not so much that he’s soliciting support, but he’s just sounding some of us out.”

Democratic governors of red states are unhappy with the idea of Dr. Dean taking over the national committee. They favor Mr. Vilsack; a former Georgia governor, Roy Barnes; or a former South Carolina governor, Jim Hodges.

While Dr. Dean has been quicker off the mark than his rivals for the post, Mr. Vilsack is now said by aides to be lobbying hard.

Senator Nelson of Nebraska, who supports the Iowa governor, argues Mr. Vilsack would be a better choice than Dr. Dean. “Midwesterners can establish that the Democratic Party is not devoid of values and is strong on many of these issues that are important to people,” he said.

The next party chairman must be in place by March 1. To get elected, the chairman needs the votes of a majority of the national committee’s 447 members, most of whom are elected by region.