The Senate on Tuesday night easily passed an amendment to credit card reform legislation that would allow concealed weapons in national parks. The vote was 67 to 29.

The question now is this: Will a controversial gun proposal attached to popular underlying legislation be the poison pill that sinks that larger bill? That’s been the case with legislation allowing the District of Columbia a voting representative in Congress, to which the Senate attached language scrapping many of Washington’s strict gun control laws. As a result of that gun amendment, the DC-vote bill remains stalled in the House months after it passed the upper chamber.

Now, Sen. Chris Dodd (D-Conn.), the chief sponsor of the credit card reform bill, is wondering whether the same might be the fate of his credit card proposal. “My concern is about what the underlying bill — what happens to it,” Dodd said on the chamber floor just before the vote. “I hate to see us lose this opportunity to make a difference with credit card reform.”

Sen. Tom Coburn (R-Okla.), who sponsored the concealed weapons bill, said he supports many of Dodd’s credit card provisions, and didn’t have in mind to offer his amendment just for the purpose of killing the larger bill. “I don’t want to see it fail on this,” Coburn said. “But nor do I want to see the Second Amendment trampled on.”

So much for an easy, clean, must-pass credit card reform bill.