When you see Democrat Majority Leader Harry Reid standing on the Senate floor this morning congratulating his Republican challenger for the Nevada Senate seat, Sharron Angle, don't be fooled. In Sen. Reid's Machiavellian mind -- and I say that as a compliment -- he is the lion congratulating the lamb on arriving in the jungle.

It was a good day for Democrats on what’s been dubbed another “mini-Super Tuesday’ and the outcome in Nevada illustrates why. Sen. Reid can't get his re-elect numbers over 50 percent as an incumbent, power player with big campaign money, the federal budget at his hand and the White House on speed dial. His state has a big hangover from the excesses of the recession in the form of foreclosures and declines in tourism.

If Republicans had nominated a mainstream Republican with name recognition to capture independents and conservative Democrats it was game over, craps for Sen. Reid.

Instead his opponent will be Angle, a Tea Party favorite who is endorsed by Sarah Palin. She is viewed as lacking name identification, money and experience. Sue Lowden, the former TV anchor, was well known and Danny Tarkanian has his famous coach-dad's name. Angle's strongest point is her passionate support from people who want to throw out incumbents, especially the Senate majority leader.

But while the Tea Party distaste for health care reform, rising deficits, and fear of tax hikes remains widespread the American public's embrace of the Tea Party is ebbing in recent polls. The ABC News/ Washington Post poll released this week now has "half the population now expressing an unfavorable impression of the loosely aligned protest campaign that has shaken up politics this year."

So you can imagine the upcoming campaign ads that ask Nevada voters if they want the devil they know or the devil they don't know. Angle will be painted as passionately angry but inexperienced and a naif in the halls of state and national power politics.

Sen. Reid has new life thanks to Angle's win and it is already showing up in Nevada polls which show him on the rise.

The same positive political dynamic for Democrats is at play in Arkansas where two-term Sen. Blanche Lincoln survived a primary challenge that reshaped her as a true moderate for a truly moderate state.

If Lt. Gov. Bill Halter had won the nomination there was no way he could have run as anything but a left-wing Democrat with inescapable financial ties to unions and support from MoveOn.Org. Congressman John Boozman who is still the big favorite but as former President Bill Clinton said after Lincoln's win the two-term incumbent is now the new come-back kid! She is going to get Arkansas voters to take a new look at her and that may lead them to recall why they like her and have twice elected her to the U.S. Senate.

And the same good news for Democrats applies in the California race. Carly Fiorina, the former Hewlett-Packard CEO, spent a ton of money to win. She has more money to spend in the general election. But as compared to the candidate she beat for the nomination she is not as attractive to swing voters. Rep. Tom Campbell, her GOP challenger, is a well-known candidate with established ties to the gay community and Hispanics.

Fiorina does not have the same allure for independents and conservative Democrats, people angry at big spending, big taxes and Washington's failure to deal with big issues such as immigration. Fiorina's history as Hewlett-Packard also has its downside, damaging her claim to be a wise hand at business who is willing to bring her expertise to government.

Republicans had the senate seats in Arkansas, California and Nevada targeted as good bets for their side in this season of anger at incumbents. But with the ABC-Post poll now showing 60 percent disapproval for Republicans in Congress and the same poll finding that Democrats “hold a double-digit ledge over the GOP as the party at people trust to handle the country’s main problems,” the political playing field for the fall does not appear as favorable for Republicans as it did a few months ago.

And after Tuesday’s races put relatively weak Republicans in position as challengers, Democrats had more reasons to remind the GOP to not be so quick to count their chickens before they hatch in November.

Juan Williams is an NPR senior correspondent and Fox News contributor.

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