Lots of sites have rundowns of the most important races to watch -- so many that it's hard to keep all the lists straight. Here are some of the common themes from those guides to help you sort out tonight's election results.
Open Season on Incumbents?
Unions and liberal groups have been spending heavily against Lincoln because she didn't support a public option in the health care reform bill and opposed pro-union legislation.
If she loses today, she would be the third member of the Senate to be ousted before the general election -- joining Utah Republican Bob Bennett and Pennsylvania Democrat Arlen Specter. Two House incumbents -- Democrat Alan Mollohan of West Virginia and Republican Parker Griffith of Alabama -- have also been booted in primaries so far. Arkansas political insiders expect Halter to beat Lincoln by at least 5 points, Politico's Mike Allen reports.
Iowa's Republican gubernatorial primary "should shed some light on just how strong the 'out with the old' sentiment actually is," according to Time. Terry Branstad, who served as governor from 1983 to 1999, is "the definition of Establishment" at a time when that label has hurt other candidates. Yet Branstad appears headed for victory over his more conservative GOP rival Bob Vander Plaats.
In California, Jerry Brown has a lock on the Democratic nomination for the job he held from 1975 to 1983. Although the guy once known as "Governor Moonbeam" was never seen as an establishment figure, he's anything but a newcomer. But it's been so long since he was in office, Politics Daily's Carl Cannon notes, many California voters might not even remember that the 72-year-old used to be governor. Former eBay CEO Meg Whitman is expected to win the GOP nomination today to face Brown in the fall.
A Washington Post-ABC News survey released today shows anti-incumbent sentiment at an all-time high. Only 29 percent of the Americans polled said they're inclined to re-elect their member of the House in November. That's even lower than in 1994, when 40 years of Democratic control of the House ended.
But True/Slant's Jamelle Bouie argues that other numbers tell a different story. He cites research from the University of Virginia's Center for Politics that says only about 40 House seats -- about 10 percent of the chamber -- are truly in play this year. If 90 percent of representatives are going to keep their seats, Bouie says, "then it is absurd to describe the nation as possessed by an 'anti-incumbent' mood."
As Bouie sees it, what's most important to voters isn't incumbency, it's the economy.
"Incumbents unlucky enough to be of the majority and in office during the recession will probably lose, and candidates savvy enough to capitalize on discontent with the economy will probably win. Simply put, the economy is all that matters for most people, and the rest is just noise." Bouie wrote.
All of the biggest races to follow as results roll in tonight feature women.
Along with Lincoln and Whitman, former Hewlett-Packard CEO Carly Fiorina (of "Demon Sheep" ad fame) is leading the field of Republicans who hope to unseat Democratic Sen. Barbara Boxer in California.
In neighboring Nevada, former state GOP chairwoman Sue Lowden and Sharron Angle, who's backed by tea party groups, are battling for the Republican nomination to challenge Senate Majority Leader Harry Reid.
The woman who's drawn the most attention in recent days is Nikki Haley, the new star of what Politico's Charles Mahtesian calls "South Carolina's freak show politics." Haley has the endorsement of Sarah Palin and current Gov. Mark Sanford, who self-destructed when his affair with a woman in Argentina was revealed last year. She's pulled ahead of her male rivals in the crowded Republican gubernatorial primary race as she fends off allegations of infidelity. Haley's biggest challenge today is winning more than 50 percent of the vote to avoid a June 22 runoff.
If Haley gets the nomination, she'll be the heavy favorite to win in the fall, Mahtesian predicts, and she will become "one of the hottest properties in the Republican Party."
Tests of Tea Party Strength
Another contest in South Carolina is a showcase for the tea party's challenge of the Republican establishment. In the 4th Congressional District, Rep. Bob Inglis is under fire from the right for supporting the 2008 bank bailout and saying last year that people should "turn Glenn Beck off." Tea-party-backed Trey Gowdy is likely to beat him, either today or in a runoff, according to Time.
It appears tea partiers won't be able to push gubernatorial candidate Steve Poizner over the top in his race against Whitman, but the movement might still influence who replaces Arnold Schwarzenegger as governor of California.
"Poizner's challenge ... did force Whitman to abandon the technocratic, centrist tone of her early positive ads, and she's lost some serious ground to Democrat Jerry Brown in recent general election polls, particularly among independents and Latinos," reports Ed Kilgore of FiveThirtyEight.com.
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"The prospect of the tea party candidate bringing her ideological baggage into the general election even has conservatives worried about a Rand Paul-like crackup," says The Daily Beast's Samuel P. Jacobs.
Angle's GOP opponent Lowden has also taken her licks in the media for urging people to barter chickens for health care. And a nasty e-mail exchange that's just come to light shows tea party groups are not unanimous in their support for Angle.
"This race has gotten so ugly, there's a chance that 'None of the above' -- always present on Nevada ballots -- could well win," according to Time.
While Angle may have an advantage in the primary, a Las Vegas Review-Journal poll indicates one of her more moderate GOP rivals, Danny Tarkanian, would have a better chance of beating Reid in the fall.
There's a similar quandary in Virginia's 5th Congressional District, where seven Republican candidates -- several with tea party backing -- are battling to take on Rep. Tom Perriello, a freshman Democrat who's seen as especially vulnerable because of his vote in favor of health care reform. State Sen. Robert Hurt, a GOP insider, is expected to win tonight because the tea party movement has not united behind a single candidate.
"A Hurt win would without question represent an establishment of triumph, a victory for the political pros who rank ideological purity after electability in assessing candidates," says Politico's Mahtesian. "And it would also showcase the challenge tea party activists are now facing -- how the lack of a central guiding organization is hampering their efforts and splintering support."