The banking industry’s reputation in Washington has taken a beating in recent years, putting the sector on what seemed like permanent defense. But when it comes to the JOBS Act, the bankers are back.

“It’s not very often this industry has been able to go on offense,” one financial services industry lobbyist said. “And it’s not because they’ve been coerced into it. They believe through and through this is all good policy, and they’re happy with it.”

All week, banking lobbyists have been writing letters to Members in support of the measure and, more quietly, lobbying for its passage in the House and for a companion bill in the Senate. The House passed the bill 390-23 earlier today, and with the Obama administration’s backing, industry lobbyists say odds are in their favor for the bill to make it to the president’s desk.

The bill is designed to make it easier for small businesses to raise capital.

“There are not too many opportunities for any industry to have bills come before Congress,” said James Ballentine, chief lobbyist for the American Bankers Association. “It’s always better to support something than to have to oppose something.”

In a letter Wednesday, Ballentine detailed the ABA’s support for the JOBS Act by noting that one part would raise the shareholder threshold for registrations with the Securities and Exchange Commission from 500 shareholders to 2,000 shareholders.

“This change would enable community based banks to deploy their capital in lending, rather than spending it on regulatory requirements that provide little incremental benefit to the banks, shareholders or the public,” Ballentine wrote to House Members.

Another group, the Financial Services Forum, also has been lobbying for the bill, including working with the office of House Majority Leader Eric Cantor (R-Va.), the Senate Banking panel and key Members. The forum’s president and CEO, Robert Nichols, wrote to Speaker John Boehner (R-Ohio) on Wednesday: “The legislation will help small business startups raise capital, spur growth, and create jobs for America.”

On the Senate side, Ballentine said, “There are great efforts under way to make the bills as similar as possible.” The ABA is advocating for as clean a bill as possible, he added.

Senate Majority Leader Harry Reid (D-Nev.) said today that he does plan to try to move a Senate version of the small-business bills and plans to go to conference committee.

“The House bill is not perfect, and we are going to try to do something here to match and get to conference and get this done,” Reid said. But before that comes up in the Senate, Reid said he will first take up the nominations of 12 judges and either a postal reform bill or cybersecurity legislation.

That delay may be caused in part by the controversy the bill has managed to attract on K Street.

Credit unions, for example, have been pushing the Senate to include a provision that would raise their member business lending cap — something the banks, not surprisingly, vigorously oppose.

“The case we’re making is that we have something that puts money in the hands of small businesses,” said Brad Thaler, vice president of legislative affairs for the National Association of Federal Credit Unions. “We think it should be included in the package … or be offered as an amendment on the floor.”

But Ballentine said that adding the credit union business lending matter to the JOBS Act would make “a noncontroversial bill more of a controversial effort,” and he has been urging Senators not to side with the credit unions.

One well-placed lobbyist said that both Reid and Sen. Charles Schumer (D-N.Y.) are working to get a bill, but that some “Republicans will be upset that it’s not going through the [Banking] Committee.”

“Republicans are generally OK with these bills,” this lobbyist said. “But going through the committee would take time, and the leadership is trying to keep the bill clean.”