WASHINGTON — Coming off a resounding defeat in Congress a year ago, the country’s top poker players are trying their hand at a time-honored Washington parlor game: lobbying.

Nearly 100 leading card players are flying into the nation’s capital this week to urge lawmakers to roll back a ban on Internet gambling. They are led by Senator D’Amato, the New York lawmaker turned lobbyist who serves as chairman of the Poker Players Alliance.

The group is pushing a bill that would legalize and regulate online gambling through the federal government, effectively reversing a law that President Bush signed last year making it illegal for American banks and credit card companies to process online bets.

“We shouldn’t be making criminals of people who want to play poker in their own home. It’s ridiculous,” Mr. D’Amato said in a telephone interview.

The former three-term Republican senator brings added political clout to an industry that says it was broadsided by last year’s legislation, which was added to an unrelated port security bill and passed overwhelmingly. “They snuck the bill through,” Mr. D’Amato said.

The poker professionals in Washington this week include Chris Moneymaker, Howard Lederer, and many others who have become celebrities thanks to ESPN’s exhaustive televised coverage of the “World Series of Poker” events. They have scheduled dozens of meetings over two days with members of the House Financial Services and Judiciary committees, along with a public forum on Internet poker.

While Mr. D’Amato said this is the first organized lobbying effort by the group, he envisions the poker alliance having a much larger political presence in the months to come; he said he wants to create a political action committee and start voter registration drives.

“There is a growing constituency and a voice that cares about their ability to enjoy poker on the Internet,” he said. “We’re going to demonstrate to the members that this awareness translates into votes.”

The 2006 ban exempts horseracing, lotteries, and fantasy sports, leading to calls of unfair treatment from poker players. The alliance claims 800,000 members nationwide, although that number includes many who were enrolled for free through participation in online poker tournaments.

The renewed push is welcome news to the sponsor of the legalization bill, Rep. Barney Frank, a Democrat of Massachusetts, who says he has had trouble building support for his proposal. “We’re not in great shape now,” he said in an interview. He added: “I need some lobbying help.”

Mr. Frank, the chairman of the House Financial Services Committee, said that while he has seen a shift from some of the more than 300 House members who supported the ban, his effort has had little help from online gamblers themselves, who, he noted, do not exactly have a history of political activism. “Playing poker on the Internet and watching C-Span are not always in tandem,” Mr. Frank said.

Raising the stakes is an earlier ruling by the World Trade Organization, which said America’s Internet gambling law placed the nation in breach of trade policies, with penalties that could total in the billions.

Republicans had long pushed for a curb on Internet gambling before they finally succeeded in enacting the legislation shortly before they lost control of Congress. Proponents cited moral concerns, saying the industry preyed on children and compulsive gamblers, and that it fostered money laundering and organized crime. As many as 23 million Americans bet online, spending about $6 billion annually, according to a congressional estimate last year.

The practice had already sparked a legal dispute, with the Department of Justice contending that online gambling was already outlawed under the 1961 Wire Act, which bars betting across telephone lines. In the midst of the legislative debate in Congress last year, high-ranking officials at two top gambling Web sites, Sportingbet and betonsports, were arrested. Though many firms were headquartered offshore in places like Costa Rica or Antigua, the bill cracked down on Internet wagers by prohibiting banks and other financial institutions from handling payments on such betting.

Enactment of the bill roiled the industry, causing some large public companies, such as PartyGaming and Sportingbet, to suspend their business in America while others, like Pokerstars.com, defied the ban and refused to fold.

Critics liken the ban to Prohibition and say it merely forces online gambling underground. “As well-intentioned as it may have been, it does not protect children, and it takes away the rights of millions of citizens of this country,” said Mr. D’Amato, an avid poker player who used to hold games with fellow lawmakers and staffers while they waited for later votes at the Capitol.

Mr. Frank’s bill, introduced earlier this year, would create a licensing system to regulate Internet betting through the Treasury Department. The proposals would mandate that Web sites implement safeguards against underage and compulsive gambling, such as identification requirements and limits on the amount and frequency of wagers. The government would also take a cut of the winnings under the bill through a tax that could provide a possible annual revenue stream of more than $3 billion to the federal coffers, according to an estimate cited by the Poker Players Alliance.

There is no estimate, however, on how much it would cost to administer and enforce the new regulations. The alliance also is supporting a narrower proposal by Rep. Robert Wexler, a Democrat of Florida, that would classify poker, chess, bridge, and mah jong as “skill games” and exempt them from the gambling ban.

The American Gaming Association, the lobbying arm of casinos, has taken no position on the proposals, nor has the National Council on Problem Gambling. The council’s executive director, Keith Whyte, said none of the bills, including the one enacted last year, devote any money to combating gambling addition. “It was a bill that dodged all the major issues,” he said of the ban.