Washington (CNN) - As the Tea Party Express gears up to reveal what it's calling a "surprise" endorsement Wednesday, CNN has learned who will receive the group's first Senate endorsement for the 2012 cycle.
The Express will endorse Nebraska's Republican Attorney General Jon Bruning in the race to unseat Sen. Ben Nelson - the state's most powerful Democrat.
"Bruning is a principled conservative that we think will represent the fiscal interests of the Tea Party," the group's national spokesman Levi Russell told CNN.
The group will officially unveil its first endorsement at a news conference at the National Press Club on Wednesday morning. The Express promises that the event will feature a "surprise," later revealed to be Bruning's appearance there.
And yet part of the surprise, to some, is that the Express will buck its trend of picking non-Republican establishment candidates in favor of a man seen as part of the GOP establishment.
Bruning has been elected three times as attorney general and previously ran for Senate in 2007.
The endorsement is sure to spark national attention and benefit Bruning.
But given the political fortunes of some past recipients of Tea Party Express endorsements, it could also be the political kiss of death for his Senate bid.
Two other Republicans have also entered the Republican race: State Treasurer Don Stenberg and businessman Pat Flynn.
Russell explained why Bruning won the endorsement.
"We had been watching him for a while," he said. "He really stood out as being a principled candidate and also having what it takes to win."
Bruning firmly embraces many of the Tea Party's goals.
He is for the repeal of the nation's new health care law, hopes to reduce the size and scope of government, espouses a firm adherence to the Constitution and stands staunchly against excessive federal spending and a growing deficit.
"What you'll start to see, in the Nebraska race, is us getting involved and starting to spend money and run ads to support Bruning and go after Nelson," Russell said.
The Tea Party Express endorsement will almost surely increase financial contributions to Bruning's campaign, cement perceptions that he is the frontrunner in the race and bring more momentum and visibility to his campaign.
With legions of supporters, the Express holds sway with many voters and has gained attention for its cross-country bus tours.
And yet its track record of Senate success is thin.
In the last cycle's Senate races, the Tea Party Express endorsed Republicans Christine O'Donnell for Delaware, Sharron Angle for Nevada and Joe Miller for Alaska - helping each win tough Republican primaries.
But all three became lightning rods of controversy and ultimately lost their general election races.
Meanwhile, the endorsement is frustrating some of Nebraska's local Tea Party groups.
James Mason, the state coordinator for the Nebraska Tea Party Patriots, said he is "outraged" over the Express endorsement.
The group "has no vested interest here in Nebraska. They have no operations or chapters of any kind in Nebraska," Mason said.
Mason also expressed dismay at the location of the endorsement announcement.
"We feel like if an announcement's going to be made, and the Tea Party Express is doing this, they should kick it off in Nebraska," he said.
Charging that the Express is "about making money," Mason added, "They want to impress donors and the media with their operation."
Another Nebraska Tea Party member echoed similar sentiments.
David West is affiliated with the NebraskaTeaParties.com, an aggregator of different Tea Party events across Nebraska and western Iowa.
"Our primary is not until May of next year," West said.
"We have a long time to go before jumping in, at this point and time, when we don't even have all the candidates announced. It's a mistake."
"They (the Tea Party Express) really, honestly, don't have a grasp of what's going on in this state. They don't know what other groups are involved in, in this state. We have at least six, seven even more Tea Party groups in the state. They never consulted or talked to any of us."
West also complained about the announcement not being made in Nebraska - and theorized that it could help the Express more than it might help Bruning.
"It's going to get them (the Express) more money, nationally, for their efforts. But is it going to affect the actual people that are on the ground that are going to be making the fight against Ben Nelson? I don't think it's going to make that much of a difference at all," West said.
Russell responded to the criticism.
“We have steady communication with tea party members in Nebraska, but we don't make our decisions based on any individual group. We also do not tell other tea party groups what to do or who to support,” he said.
As for announcing the endorsement in Washington D.C., Russell said, “The Senator from Nebraska will cast votes on legislation that affects every American. We felt it was appropriate to deliver the message to a national audience that Jon Bruning is going to be the next Senator from Nebraska, and ask tea partiers across the US to support him.”
And regarding the early nod, the Express spokesman said it will take time to defeat the formidable incumbent senator.
“Defeating Ben Nelson is critical, and we want to give him [Bruning] maximum advantage in running an effective campaign with our support,” Russell.
Earlier this year, the Express named Nelson as one of its top political targets, claiming that the senator sells out his vote.
The two-term incumbent has helped President Barack Obama achieve some policy goals, particularly casting a key vote for health care reform during the legislative debate over it.
Claims that Nelson sells out his vote is merely "poppy cock and political rhetoric," Nelson's campaign manager Paul Johnson told CNN.
CNN is teaming up with the Tea Party Express for a first-of-its-kind presidential primary debate. The Tea Party debate, featuring 2012 Republican presidential candidates, is scheduled for Labor Day week 2011. It will take place in Tampa, Florida – the site of the 2012 Republican National Convention.
CNN is partnering with the Tea Party Express for the first-of-its-kind GOP presidential primary debate in Florida.
Follow Shannon Travis on Twitter: @ShanTravisCNN