Sarah Palin is going to bat for long-shot candidate Rob Maness in Louisiana's race to determine which Republican will challenge Sen. Mary Landrieu.

Maness, a retired U.S. Air Force colonel, commanded 4 percent of the vote in an April New York Times poll. And a Huffington Post poll tracker updated two weeks ago gave him 4.1 percent of the vote, just shy of fellow Republican Paul Hollis and bounds behind Rep. Bill Cassidy, who clocked in with 22 percent of the vote.

On a conference call with reporters, Maness said he expects momentum to build.

“This has been a great day,” he said. “Very, very grateful for Gov. Palin’s endorsement.”

He said he had nearly 100 percent positive response from donor calls Thursday.

Palin's endorsees for this cycle haven't all fared well. Her first of the cycle, Katrina Pierson, lost to Rep. Pete Sessions in the Republican primary for Texas' 32nd district, garnering 36 percent of the vote. In the Republican primary for North Carolina's third district, her candidate Taylor Griffin lost to incumbent Rep. Walter Jones with 45 percent of the vote. And in the primary for Florida's 19th district, Curt Clawson defeated Palin endorsee Lizbeth Benacquisto, 38 percent to 26 percent.

Her Senate picks seem to be doing better. T.W. Shannon, Ben Sasse and Karen Handel have all seen their poll numbers go up after receiving the Palin endorsement.

Palin isn't Maness's first high-profile conservative endorsement; the Senate Conservatives Fund endorsed him in October, and the Madison Project PAC supports him as well.

Cassidy's campaign didn't comment on the endorsement. When Sen. John McCain chose her as his running mate in 2008, Cassidy had high praise for the then-Alaska governor. Cassidy was running for his first term in the House at the time, and released a glowing statement on McCain's pick.

“As a conservative reformer, I applaud the bold decision by Senator McCain to choose Governor Sarah Palin as his running mate,” he said. “Governor Palin has stood up to Congress and refused wasteful earmarks sent to her state, like the infamous ‘bridge to nowhere.' She has challenged politicians, even within our party whose unethical behavior and coziness with special interests didn't reflect the proper role of a public servant. Her resolve in fighting corruption and wasteful spending is desperately needed in Washington DC.”

Palin's Facebook post endorsing Maness had strong criticism for Cassidy, who she described as “a moderate Congressman who opposed President Reagan in the past and was actually a supporter of Mary Landrieu until recent years.”

“Come on, GOP, is this the best we can do?” she wrote.

Maness said he met Palin at a book-signing in Monroe, La., in December.

Election Day in Louisiana is Nov. 4. If no candidate gets more than 50 percent of the vote, then the top two vote-getters will head to a runoff.