clean bill とは？

以下は3日付web版CNNの新年度の予算案が議会を通過しないのでアメリカ政府がshutdownしたという記事の一部です。最後から2番目のパラグラフにある　he was willing to allow a vote on a clean bill. という文章中のbillは法案というのは分かりますが、clean billというのは何の事でしょうか？
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Washington (CNN) -- A small but growing group of House Republicans is increasingly worried about the fallout from the government shutdown and say it's time for Speaker John Boehner to allow a simple vote on a spending bill.
Defunding Obamacare can wait for now, they say.
"I'm trying to be optimistic but at the same time I have a really, really tough time when people are out of work and they can't pay their bills," Rep. Michael Grimm of New York told reporters Wednesday. "Though it might be a political loss for us ... this is an untenable situation."
Rep. Scott Rigell, whose Virginia district is home to a significant number of military members and civilian contractors, was one of the first to publicly break away.
"We fought the good fight," he said in a tweet on Tuesday, but acknowledged it was time to move on.
Boehner hosted small groups of concerned members on Wednesday. A spokesman for Boehner declined to talk about the sessions.
A Republican source familiar with one of Wednesday's meetings said Boehner listened, but didn't signal he was willing to allow a vote on a clean bill.
"They weren't strong-armed, and they weren't asked to step back," the source said of the moderates in the meeting. It was taken as a positive sign that Boehner wasn't trying to muzzle the effort.
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No.1 ベストアンサー 回答者： ddeana 回答日時： 2013/10/04 20:27

クリーン法案といいますが、様々な条件を加えない純粋な予算法案のことです。