Fresh off big primary wins in Delaware and Alaska, national "tea party" groups are redirecting the energy of the movement toward the November midterm elections, raising millions of dollars, expanding their advocacy into dozens of congressional races and building voter turnout operations nationwide.

Leaders of the Atlanta-based Tea Party Patriots announced a $1 million donation Tuesday, from an anonymous single contributor, that the organization will pour into local tea party groups and get-out-the-vote efforts in some of the most competitive congressional races.

FreedomWorks, which is headquartered in Washington and endorsed 25 House and Senate candidates during the primary season, said it will expand that list to more than 80. The Tea Party Express, based in Sacramento, is planning its largest national bus tour at the end of October to get conservatives to the polls.

The goal is to keep alive the momentum the movement has generated and to use it to target vulnerable Democratic candidates.

"People are starting to realize that the tea party represents a powerful get-out-the-vote machine," said Matt Kibbe, president of FreedomWorks. "We've got the most energized voting constituency in the country. This movement has been organizing since before April 2009, and all of that community is energizing and driving public opinion. The establishment is taking us more seriously. There's nothing like turning out votes in an election that matters."

The new push illustratesthe movement's transformation since the primaries from a disorganized coalition of fiscally conservative activists to a measurable political force. But the tea party's rapid growth - along with the influx of cash and political professionals - has led some followers to worry that it risks losing its rebel spirit.

"Many of the grass-roots activists who started this movement 18 months ago, myself included, may look and ask the question 'Dude, where's my movement?' " said Judson Phillips, founder of Tea Party Nation, which held the movement's first large-scale convention this spring. (Another scheduled to be held in Nevada next month has been cancelled.) "There is no question the movement has changed. The evolution of 'Big Tea' is the logical result of where this movement must go."

Equally uncertain is whether the movement's success with activist primary voters will play as well with the broader general electorate in November. Most polls show that at least as many registered voters view the tea party unfavorably as favorably.

Perhaps no group is more aware of the divisions within the movement than FreedomWorks, a tea party organizer headed by Richard K. Armey, a former corporate lobbyist and congressman from Texas who was once House majority leader. FreedomWorks has taken a politically pragmatic approach in deciding which candidates to endorse. In last week's Senate primary in Delaware, Tea Party Express spent more than $200,000 on behalf of Christine O'Donnell, who was challenging Rep. Michael N. Castle, the establishment GOP choice. But FreedomWorks' leaders declined to back O'Donnell because they didn't think she could win the general election in November.

Yet FreedomWorks, which focuses primarily on training volunteers and helping them organize phone banks, door-knocking campaigns and other voting-related efforts, is eager to take advantage of the momentum from O'Donnell's victory - and also from that of Joe Miller, who beat incumbent Lisa Murkowksi in Alaska's Republican Senate primary last month. FreedomWorks endorsed O'Donnell the day after her win, and, this week, the group plans to announce that it will back the Senate campaigns of Linda McMahon in Connecticut, Carly Fiorina in California and John Raese in West Virginia.

FreedomWorks and other tea party groups are expanding their lists of approved candidates to include more establishment-backed Republicans. The intention is to rally tea party activists behind all Republicans this fall and not just those who identify with the movement.

"We've gone through the primary process," Kibbe said. "I think the tea party has had a tremendous impact on the quality of the candidates coming out of the primaries. But here we are in the race to November 2, and November 2 is all about holding Democrats accountable."

Amy Kremer, chairman of the Tea Party Express, distanced her organization from that general-election strategy, noting that the group identified its "heroes" and "targets" on April 15 - and that it is not wavering from the list.

"There may be some groups that need to reevaluate where they are, but we're not doing that," she said. "We've helped Joe Miller in Alaska and Sharron Angle in Nevada and Christine O'Donnell in Delaware come across the victory lines, and we're behind them 100 percent going into November."

Both national political parties are struggling to adjust to the tea party's continued prominence. Eric Schultz, a spokesman for the Democratic Senatorial Campaign Committee, said the party welcomes the nomination of tea-party-backed candidates in Senate races nationwide. He noted that in most of the states holding those elections, notably Kentucky, Nevada and Delaware, those candidates have helped Democrats remain competitive in races in which they were expected to struggle.

"We are more competitive in these races because they nominated candidates who are extremists," Schultz said.

Still, Democrats must contend with perhaps the biggest strength of the tea party movement, which is its ability to get conservatives to vote. GOP leaders have bristled at the tea party's willingness to overthrow establishment candidates, but no one doubts the boost that the movement will give Republicans in November.

"That's not a bad trade-off, considering that we have this tremendous energy and enthusiasm moving into the fall," said Brian Walsh, spokesman for the National Republican Senatorial Committee. "I would take any one of our candidates over a candidate on the Democratic side who voted for the stimulus bill, who voted for the health-care bill, and whose message is 'If you vote for me, I'm going to vote for the status quo in Washington.' "