Senate Majority Leader Harry ReidHarry ReidChris Murphy’s profile rises with gun tragedies Republicans are headed for a disappointing end to their year in power Obama's HHS secretary could testify in Menendez trial MORE (D-Nev.) blamed Republican Senate candidate Scott Brown for the stalling of a bipartisan energy efficiency bill.

Brown is running for Senate against Sen. Jeanne ShaheenCynthia (Jeanne) Jeanne ShaheenHomeland Security searching some social media doesn't violate privacy The feds shouldn't blackball Kaspersky without public evidence Week ahead: Crunch time for defense bill’s cyber reforms | Equifax under scrutiny MORE (D-N.H.), the lead sponsor of the energy efficiency bill with Sen. Rob Portman (R-Ohio). Brown previously served as a U.S. senator for Massachusetts, but now lives in New Hampshire.

Shaheen and Portman's bill failed to get enough Republican support to overcome a filibuster on Monday.

Republicans blamed Reid’s refusal to consider any amendments, but Reid said Republicans blocked the bill because Brown requested it.

“Scott Brown, who is running for the Senate in New Hampshire, he asked the Republican caucus to make sure they didn’t give Sen. Shaheen a win on this,” Reid said on the Senate floor Thursday. “I wonder who called them today to tell them to kill this bill … maybe it’s one of the other Republicans wanting to join the Senate.”

Reid’s comment came immediately after Republicans also blocked progress on a tax extender bill, which had broad bipartisan support. But Republicans again were unable to offer amendments.

Republican National Committee spokesman Jahan Wilcox said Reid would say anything to protect Shaheen in her reelection. Senate Democrats are defending several vulnerable seats and could lose control of the chamber.

“Senator Harry Reid is willing to go to great lengths to protect his liberal protégé Jeanne Shaheen who blindly supports him and President Obama’s agenda" Wilcox said. "While Reid continues his casual relationship with the truth, the fact is Shaheen voted for Reid’s poison pill that killed the Keystone XL pipeline.”

Shaheen voted to end debate on the motion to proceed to her bill. Republicans said Reid filing that motion without allowing any amendments is what killed the deal. But Reid said the deal was to hold a vote on construction of Keystone in exchange for passage of the energy bill and Republicans reneged.

— This article was updated at 5:45 p.m. to include comments from the RNC.