Appearing on CBS' "The Early Show" this morning, Dan Bartlett said, "The Tea Party and whoever else assembles with the Tea Party, like they did this weekend, is demonstrating that Republicans in this election cycle coming up in November have that advantage.
"In midterm elections, that is a crucial difference."
In several primaries so far, Tea Party-backed candidates have unseated Republican establishment candidates in Kentucky, Florida, Utah, and South Carolina. In Alaska's Senate primary, the votes are still being counted but the Tea Party candidate Joe Miller has the edge over incumbent Republican Senator Jill Murkowski.
At Beck's rally, participants said they came "to support conservatism, low taxes, small government."
Another predicted, "That is going to translate to the booth in November."
But if Miller wins the Republican nomination, he may face a tougher fight in the general election, having campaigned on privatizing Social Security. Like other candidates, he may have to tack closer to the center to win.
Bartlett said this morning that the Tea Party activists have been and will continue to be crucial to Republicans for doing "a lot of the hard spade work" like passing out bumpers stickers and putting up yard signs. "That's a critical part of the midterm election," he said."
But more critical to a Republican victory, Bartlett said, is how the anger of Tea Partiers combines with issues that could damage Democrats: a bad economy and Afghanistan. "That is a very toxic combination for Democrats as they go into November, and these Tea Party activists are the ones who are stirring it up," he said.
When asked about the influence of former Alaska Gov. Sarah Palin, who has campaigned and helped raise funds for several successful Tea Party candidates, Bartlett said she is making her mark in backing primary winners, adding "there's very narrow differences with regards to the number of people who can make the difference."
But he believed her track record as a king- or queenmaker is not easily translatable to her own presidential ambitions.
"I think if you start moving beyond the midterm election and start to try to galvanize a national movement in a presidential election, it's going to be far more difficult for her organizers to have that greater impact," he said.
CBS News correspondent Nancy Cordes reports the crowd at the rally Saturday fell into two categories: Tea Partiers who told her they want to drastically lower taxes, and Christian conservatives calling for a much greater role for religion in public life.
And if Republicans ride a wave of Tea Party enthusiasm back into power this Fall, it's the Tea Party activists to whom they'll have to answer. Ironically, the GOP might find itself in a position similar to one President Obama now faces with his supporters on the left:
"When Republicans get into power, that group of activists could want more from them than they can ever deliver," said CBS News political analyst John Dickerson.
More Coverage of "Restoring Honor" Rally:
Al Sharpton Leads Activists Near Tea Partiers
Glenn Beck: "Something Beyond Imagination is Happening"
Glenn Beck's Power to be Tested at D.C. Rally
Tea Party Blogger Accused of Racism in Beck Post
Glenn Beck Rally Will Test Tea Party Strength
Glenn Beck Rally on MLK "Dream" Date Draws Fire
Glenn Beck Rally Continues to Spur Controversy