The Senate is still scheduled to take up the PROTECT IP Act next week, so the next few days will undoubtedly be about lawmakers announcing whether they are “yea” or “nay.”

Although the legislation has 40 co-sponsors, there are signs that support is eroding. The White House criticism seems to have only escalated attacks on the bill, and lawmakers are starting to view the bill as a real liability rather than a sure bet for something to show for saving jobs.

Sen. Scott Brown (R-Mass.), locked in a tight re-election battle with expected opponent Elizabeth Warren, announced on Twitter that he would oppose the bill. “I’m going to vote NO on #PIPA and #SOPA . The Internet is too important to our economy.”

Sen Patrick Leahy (D-Vt.), co-author of the bill, issued a statement defending it. “Much of what has been claimed about the Senate’s PROTECT IP Act is flatly wrong and seems intended more to stoke fear and concern than to shed light or foster workable solutions.  The PROTECT IP Act will not affect Wikipedia, will not affect Reddit, and will not affect any website that has any legitimate use.”

He added,  “Perhaps if these companies would participate constructively, they could point to what in the actual legislation they contend threatens their websites, and then we could dispel their misunderstandings.  That is what debate on legislation is intended to do, to fine-tune the bill to confront the problem of stealing while protecting against unintended consequences.”

Brown’s opposition may be an indicator of how the issue will play as an election issue, given that some of the bill’s detractors have vowed to work to defeat key supporters in Congress. The conservative Heritage Action Committee came out against the legislation on Tuesday, potentially influencing other members of Congress on the right.

Rupert Murdoch, meanwhile, is running what amounts to a running industry commentary on all the latest developments over the legislation. As news broke today of Brown’s vote and fracturing support, he wrote, “Seems blogosphere has succeeded in terrorizing many senators and congressmen who previously committed. Politicians all the same.”

Update: The response from the Twitterverse to Murdoch’s comments are hardly in agreement. A sample: “@danielthomsen Daniel T. Thomsen  @rupertmurdoch yes, utterly terrible when elected officials respond to feedback from the electorate.”