Senate Democrats remain confident that they can pass a House-passed campaign finance bill even though it contains a controversial carve-out for the National Rifle Association.

The NRA language, added to garner the support of conservative House Democrats, has drawn fierce opposition from Democratic Sens. Dianne Feinstein (Calif.) and Frank Lautenberg (N.J.), staunch gun-rights opponents. Meanwhile, Senate Republicans oppose the package, known as the DISCLOSE Act, on its face, calling it an election year ploy. The bill passed the House last month only after a major whip effort led by its chief sponsor, Rep. Chris Van Hollen (D-Md.).

As part of the sale to wary House Members, Senate Majority Leader Harry Reid (D-Nev.) and Conference Vice Chairman Charles Schumer (D-N.Y.) vowed to take the package up this month.

Schumer, former Democratic Senatorial Campaign Committee chairman and author of the Senate version of the bill, and Reid told House Democratic brass in a bicameral leadership huddle Tuesday that they are committed to forcing a vote on the measure, whether or not it has the support to clear a filibuster, sources familiar with that session said.

“We hope to consider the DISCLOSE Act in the coming weeks,” Reid spokeswoman Regan Lachapelle said. “There is no reason why Republicans shouldn’t support this legislation that will help keep foreign interests out of our elections and require disclosure of what special interests are trying to influence the public.”

Schumer and Van Hollen, who is in his second tour as chairman of the Democratic Congressional Campaign Committee, introduced the legislation earlier this year in response to a January Supreme Court decision lifting limits on outside spending that they argued would lead to a flood of hostile corporate money against the party. The House narrowly passed its version June 24 with the provision exempting the NRA from complying with disclosure requirements.

Senate Democrats hope to make good on their promise to get the bill passed, but it remains unclear whether Reid can muster the 60 votes he needs to beat back a likely GOP filibuster. Few Senators have weighed in on the House language, including Democrats who support gun rights. Sen. Jon Tester (D-Mont.) said he preferred the House language but would vote for a Senate measure that didn’t contain the NRA carve-out.

Schumer is trying to gauge the support in the Conference. Likely targets for support are Republican moderate Sen. Scott Brown (Mass.), and Maine Sens. Susan Collins and Olympia Snowe. Snowe co-authored key pieces of the landmark McCain-Feingold campaign finance reform bill and was a critic of the January Supreme Court decision in Citizens United v. Federal Election Commission.

Election reform advocates supporting the push are planning grass-roots campaigns in those two states to encourage the Senators to get on board. “Our first priority is to persuade Republican Senators to vote for this bill, and that’s what we will try to do in the [next] couple weeks,” Democracy 21 President Fred Wertheimer said. “There’s still a lot of misinformation about this bill that we have to catch up with.”

The House-passed measure is pending on the Senate calendar and could be brought up at any time. Democratic aides said there will be a July push even if the party is shy of the 60 votes needed to break a filibuster threat. Should the bill make it that far, Lautenberg and Feinstein are likely to sponsor an amendment to strip the NRA language. Still, Democratic aides predicted that both Lautenberg and Feinstein would ultimately support the DISCLOSE Act even if the NRA carve-out stands.

At the moment, however, party leaders still have some whipping to do.

“I’m inclined not to vote for anything that leaves anyone out. Either everyone’s included or no one’s included as far as I’m concerned,” said Feinstein, who recently spoke to Schumer about the bill. “I’m not convinced.”

Senate Minority Leader Mitch McConnell (R-Ky.), who has led opposition to campaign finance reform in the past, could be a pivotal figure in the debate. A senior GOP aide said, however, that McConnell won’t have to do much convincing to keep his Members unified against the bill.

“The proposal contains the worst kind of special deals and backroom exemptions,” the aide said. “It creates loopholes for Democratic allies to continue traditional campaign advocacy and silences the traditional Democratic critics, which is unbelievable at a time when Americans are so cynical about the motives of politicians in Washington.”

Tory Newmyer contributed to this report.