In a packed room of Tea Party activists, four Republican senators launched an official Senate Tea Party Caucus, a unique partisan entity in the chamber.

"Thank you for sending me some help," Tea Party darling Sen. Jim DeMint, R-S.C., beamed, as he welcomed Sens. Jerry Moran, R-Kan., Mike Lee, R-Utah, and Rand Paul, R-Ky.

No other GOP senators, of the 47-strong conference, have opted to join the group, though many profess support for the conservative movement. Noticeably absent from the gathering - Sen. Ron Johnson, a Republican who sprang from the ranks of the Tea Party movement in Wisconsin to oust an incumbent Democrat. 

Moran said he just decided Wednesday to join the Tea Party Caucus. "The issues it stands for are important to me," he told Fox. Those issues, according to organizers who addressed the group, are deficit and debt reduction and a focus on deep cuts in spending.

It was DeMint, now planning a trip to the crucial early-voting presidential primary state of Iowa, who bucked his party in the 2010 midterm elections to get a number of unknown conservatives elected.

"The half of you who understand what's going on have to be more active," DeMint pleaded, noting President Obama's climbing approval ratings. "This is literally about saving our country," DeMint said to a standing ovation in the Hart Senate Office Building.

Sen. Lee, whose support from conservatives helped him oust incumbent GOP Sen. Robert Bennett, a close friend of Senate GOP Leader Mitch McConnell, R-Ky., called for "a constitutionally-limited government" to great applause, and called Obama "one of the most liberal presidents in history."

Fiscal hawk Sen. Pat Toomey, R-Pa., the former head of the conservative Club for Growth, joined the gathering pushing his bill that would mandate that the government prioritize payment of the interest on its debt in an effort to neutralize the Administration's argument that the nation would default, risking a global crisis, if Congress does not approve an increase above the current borrowing cap of $14.3 trillion.

Toomey said he was not necessarily ruling out a vote for the increase that's tied to a mandatory deficit reduction package, but he added, "We should take off the table the false argument that failure to raise the debt ceiling means a default on our debt."

There was an awkward moment, however, as Toomey revealed off camera that he was not joining the Tea Party Caucus "as of right now." The freshman departed the meeting quickly, shrugging off reporters' questions.

It is unclear how this new caucus will interact with the GOP conference and the conservative Steering Committee run by DeMint, but Paul told the activists in the room that the group will meet quarterly and try to target meetings ahead of "big votes," like the one to increase the debt ceiling.

Those gathered heard from prominent conservatives, including Grover Norquist of Americans for Tax Reform.

Amy Kramer, a founder of the movement and head of the Tea Party Express, reminded members that the group opposes an increase in the debt ceiling, saying, "Let's have a showdown on the debt ceiling."

"Now we want to see actions. Actions speak louder than words," Kramer reminded, vowing in 2012 to "retire Harry Reid, D-Nev., as the Senate Majority Leader."