In one of the most heavily contested races today, Tea Party favorite Sharron Angle surpassed more than a dozen GOP candidates to become the Republican nominee who will face off against Senate Majority Leader Harry Reid in November.
Republicans in Nevada battled fiercely for a big prize: the chance to take on the Senate seat that Reid has occupied for more than two decades, and possibly render him the second Democratic party leader to be ousted by the Republicans in six years, after Tom Daschle in 2004.
Angle, a former assemblywoman, was in a neck-and-neck race with former state GOP chair Sue Lowden, who was favored by the state's Republican establishment.
What started off as a shoe-string campaign for Angle morphed into a million-dollar push to derail Lowden: The so-called Tea Party Express funneled half a million dollars into Angle's campaign, with hundreds of thousands more coming from other national conservative groups such as the Club for Growth.
Angle is an anti-tax crusader and an uncompromising conservative. She favors abolishing the Departments of Education and Energy, phasing out Social Security and Medicare, and removing the United States from the United Nations.
Reid's campaign views Angle's non-mainstream platform as one that can easily be targeted in the November midterm election.
Even though several incumbents have lost in primaries -- Nevada Gov. Jim Gibbons today became the first sitting governor to lose a reelection bid -- not all is lost for incumbents.
Longtime Arkansas Sen. Blanche Lincoln narrowly avoided becoming another casualty of anti-Washington sentiment, barely defeating Lt. Gov. Bill Halter, a favorite of labor unions and environmental groups in a close runoff race today.
Lincoln had slightly more than 50 percent of the votes, with Halter trailing closely behind, according to the Associated Press.
Lincoln's win is a major blow to labor unions and liberal groups, who poured millions of dollars into Halter's campaign, and in a state that normally doesn't garner this much national attention.
"The vote of this senator is not for sale and neither is the vote of the people of Arkansas," Lincoln said in her victory speech, rebuking national labor groups.
Lincoln, who won the support of both President Obama and former President Bill Clinton, was blasted by national labor unions for voting for the federal bank bailout and opposing the option of a government-run insurance plan in the health care bill and the Employee Free Choice Act, or card check, a high priority for the labor movement.
The groups wanted to paint Lincoln as an example of what would happen to Democrats who crossed liberal groups.
Lincoln's win is also a victory for Obama and Clinton, who campaigned for her in the final days of the race.
Lincoln has been in the Senate since 1998, when, at 38, she became the youngest woman to be elected. She serves as chair of several important committees, including Agriculture, Nutrition and Forestry, and the subcommittee on Energy, Natural Resources and Infrastructure.
Lincoln will face an even fiercer fight in November as Republicans take aim at her Senate record and take advantage of the anti-incumbent sentiment that has ended careers of Sen. Arlen Specter, D-Pennsylvania, and Sen. Bob Bennett, R-Utah.
The anti-incumbent sentiment accelerated the momentum among newcomers in ousting established lawmakers in Congress. At the same time, from California to Georgia, it pitted party members against each other, exposing the ideological frays within each party.
Tea Party Favorites Take Center Stage
Tea Party favorite Nikki Haley nabbed a majority of votes in the South Carolina GOP gubernatorial primary, but stopped just shy of the 50 percent of votes needed to avoid a runoff, according to the Associated Press. Nevertheless, the South Carolina primary dealt a blow to the GOP establishment in the state: Both Lt. Gov. Andre Bauer and attorney general Henry McMaster, once considered frontrunners in the race, trailed well behind Haley and conservative Rep. Gresham Barrett.
Haley and Barrett will face off again in a runoff election two weeks from today.
The divisive South Carolina gubernatorial primary was dogged by ethnic slurs -- a GOP state senator called Indian-American Haley a "raghead" -- and allegations of marital infidelity.
But Haley's popularity has risen in recent weeks, thanks to endorsements from the Tea Party in general, and Sarah Palin in particular. The former Alaska governor campaigned with Haley and recorded a telephone message calling the allegations against Haley "made-up nonsense."
Tea Party supporters also nabbed a victory in the contested runoff in Georgia, where former state representative Tom Graves defeated former state House member Lee Hawkins in a special election for the U.S. House of Representatives. Graves was backed by the Atlanta Tea Party Patriots and the conservative Club for Growth.
Still, in another key battleground -- Virginia's fifth Congressional district -- the Republican establishment's candidate Robert Hurt flew to an easy victory with 48.4 percent of the votes.
California Republican Senate Primary: November Battle of 'Scrappy' Political Women?
Ex-Hewlett Packard chief executive Carly Fiorina defeated Rep. Tom Campbell and state Assemblyman Chuck DeVore in the race to challenge incumbent Democratic Sen. Barbara Boxer in November.
Fiorina, as with Haley in South Carolina, received an unexpected endorsement from Palin even though DeVore has been supported by Tea Party groups.
Palin recorded a telephone message for Fiorina, urging voters to "help get our country back on track" by voting for the former executive.
Fiorina spent a lot of her own personal wealth on the campaign, a point likely to be seized upon by Democrats in the midterm elections. Campbell has struggled to keep pace, temporarily withdrawing television advertising last week. A libertarian on most social issues, Campbell has focused his rhetoric on his electability in the final days of the campaign.
All the candidates seized on the nation's anti-incumbent sentiment to attack Boxer, who has served in the Senate for 17 years.
California Gubernatorial Primary: Inheriting Schwarzenegger's Problems
Former eBay chief executive Meg Whitman beat state insurance commissioner Steve Poizner for the nomination to succeed Gov. Arnold Schwarzenegger, the moderate Republican governor whose tumultuous time in office is coming to an end.
Whitman spent more than $70 million of her money in her campaign to succeed Schwarzenegger, a moderate Republican.
In a bid to win over conservatives, Poizner made immigration the defining issue of his campaign, supporting the controversial Arizona law on illegal immigration and attacking Whitman for opposing it.
Whitman will face Democrat Jerry Brown, the state's attorney general, in the fall. Brown previously served as governor from 1975 to 1983.
Today's primaries could be the last to be held in the state.
A ballot initiative seeks to limit the general election to two members of the same party.
Proposition 14 would replace party primaries with a "top-two" election structure for congressional, statewide and state legislative elections. All candidates would be included in a single primary election open to all voters, regardless of party registration. Candidates would have the option to declare a party preference or appear on the ballot with no affiliation.
The two candidates with the highest vote totals in the primary would then advance to a general election. Write-in votes would be ignored. The November ballot thus could feature two members of the same party as the only options.
ABC News' David Chalian, Devin Dwyer, Alex Pepper and Jonathan Karl contributed to this report.