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Introducing the NewsHour Senate Six

Sen. Scott Brown, who won a special election in 2010 to replace the late Sen. Ted Kennedy, will face off against democrat Elizabeth Warren this fall. The contest is expected to be one of the tightest and most-watched in the country.

The presidential race is not the only contest that could change the course of the nation this fall.

The NewsHour is introducing the Senate Six — a handful of races that we’ll track most closely this election year.

A third of the Senate seats are on the ballot in November, and these six are not the only competitive races. But each of these contests will tell us a lot about the direction the nation is headed, and they will serve as the NewsHour’s guide to the battle for the majority this fall.

Republicans need just four seats to win control of the chamber, or three should they win the presidency and the GOP vice president would become the tie-breaking vote. The National Republican Senatorial Committee is ready for battle, having already reserved $25 million ads.

Our Senate Six is broken down into three categories.

True Battlegrounds: Montana and Virginia

Polls in these states have been showing virtual ties for months, and you shouldn’t expect that to change.

Montana Sen. Jon Tester came to Washington after a surprise, narrow win in 2006. He unseated Sen. Conrad Burns in a Democratic wave year. The margin was so close (less than 3,600 votes) it wasn’t declared until the day after the election, and that — coupled with Jim Webb’s Virginia victory — meant Democrats would now be in charge of the Senate.

Tester, a dirt farmer, has represented his state by sometimes going against his own party leadership, but the GOP is working to tie him to President Obama in part because of his support for the health care reform law. He’ll face Rep. Denny Rehberg, who, as the state’s at-large Congressman, has already been winning statewide races for more than a decade. Montana also is a state where television time is cheap, so voters there can expect a barrage of negative attacks from both sides flooding the airwaves from now until Nov. 6.

In Virginia, Webb is retiring after one term, and the open-seat contest has a familiar cast of characters.

Two former governors, Tim Kaine and George Allen, are locked in a tight race to replace Webb. Kaine, a close ally to Mr. Obama and the former Democratic National Committee chairman, earned a lot of credit for the Obama team capturing the Old Dominion in 2008. Allen, who was unseated by Webb by yet another razor-thin margin in 2006, wants his old job back.

With the president’s team making clear that Virginia is a must-win for his re-election, expect the Senate contest to take on national tones and implications as both parties make this the prime battleground in the fall. The question everyone will be asking: can Kaine deliver his state a second time?

Potential to Flip: Massachusetts and Nevada

Just like Virginia, the race between Sen. Scott Brown and Elizabeth Warren will take a national tone. Brown became a Republican hero in January 2010, surprising the Democrats by winning a special election to replace the late Sen. Ted Kennedy and denying the party a supermajority in the Senate.

The Democrats boast they have a candidate with appeal to liberals across the country and fundraising prowess in the Harvard Law School professor, and they know they have a turnout advantage in the Northeastern state in a presidential election year. But Brown is a dogged campaigner and remains popular back home for sometimes bucking his party on issues such as the repeal of Don’t Ask, Don’t Tell. Add to the mix that Massachusetts is Mitt Romney’s home state and the dynamics of this race get even more interesting.

Some polls put Warren in the lead, but check out the TPM Polltracker Average showing it basically tied, and expect it to stay that way until election day.

Nevada is a little more tricky for appointed Sen. Dean Heller. Heller, a former member of Congress, was named to the seat after Sen. John Ensign resigned in a scandal, and Majority Leader Harry Reid, also from Nevada, has been open about targeting Heller’s election hopes by calling tough votes. Aside from parliamentary procedures, the Reid machine is not to be underestimated. After all, he was the guy who won his 2010 Senate race with massive unpopularity against all odds, thanks in part to the rise of the tea party.

And by the way, this is a must-win state for the Obama campaign. They have invested millions in state offices, field staff and to keep a network of volunteers engaged. They also are banking on the president winning the Latino vote. If Mr. Obama is re-elected in November, it’s likely to be with Nevada in the win column, and he’s likely to sweep Democratic Rep. Shelley Berkely into the seat along the way.

Open-Seat Swing Seats: New Mexico and Wisconsin

Democrats consider these seats must-holds in November. Sen. Jeff Bingaman of New Mexico and Sen. Herb Kohl of Wisconsin weren’t surprise retirements given their long terms of service, but their exits are going to cost the Democrats money and organizing bandwidth.

Mr. Obama won both states in 2008, and the campaign is aiming to capture each a second time around.

Wisconsin is one of those battleground states with several marquee races — including a gubernatorial recall — and the contest here for the presidency should be close this fall. Democrats have won the presidential race here since 1988, but in many cases by slim margins. Tommy Thompson, the former governor and a former Health and Human Services Secretary under George W. Bush, is likely to be the Republican nominee here after a tough primary challenge from the right. With Rep. Tammy Baldwin campaigning to become the first openly lesbian senator on the Democratic side, the race already is attracting national attention from interest groups.

New Mexico is likely to be an easier feat for Mr. Obama, but we’re keeping a close eye on the Senate race as an indicator. If it gets tighter, Mr. Obama could be in trouble in the West. Two Democrats, Rep. Martin Heinrich and State Auditor Hector Balderas, are engaged in a competitive primary battle to claim the nod here. Former Republican Rep. Heather Wilson, a moderate, has a solid chance at becoming her party’s nominee.

So, what does all this mean for the overall landscape?

Races can turn on a dime, and it’s difficult to know in April how things will shake out in more than six months (Christine O’Donnell, anyone?). But the general picture isn’t great for the Democrats. They are all but certain to lose seats in North Dakota and Nebraska, conservative-leaning states where the GOP candidate will be boosted by voters who turn out to vote against Mr. Obama. If the Democrats succeed in flipping Nevada and Massachusetts, those losses are offset, but that shifts the spotlight on tough turf for the party.

If we were calling this project the Senate Seven, Missouri would be on our list. Democratic Sen. Claire McCaskill is known as a tough campaigner, but the odds are against her this year. Democrats rarely win statewide in Missouri with more than 50 percent of the vote, and she captured this seat in 2006 by the slimmest of margins to unseat Sen. Jim Talent. It’s another state where Mr. Obama’s presence on the ticket could drag down other Democrats. Republicans haven’t yet selected their nominee, which could make a difference in how this race turns.

Republicans like their chances in Missouri, and against Sen. Bill Nelson in Florida. But polls show both Nelson and Sen. Sherrod Brown in Ohio are in better positions now than they were a few months back, and they each will benefit from the Obama campaign’s statewide infrastructure and get-out-the-vote operation.

The GOP also thinks former Gov. Linda Lingle gives them a good shot at capturing an open Democratic seat in Hawaii. Given it’s the president’s home state, that’s not as likely, but we’ll keep an eye on that one, too. If Mr. Obama can possibly lose Hawaii on Election Night, the chances of Republicans sweeping the nation are pretty darn good, so it won’t be the race to wait on.

Just for fun, we’ve added a bonus state to watch: Maine.

Democrats think Olympia Snowe’s retirement means they’ll retain Senate majority by scooping up her seat in a blue state. Former Gov. Angus King intends to run as an independent, and in true independent fashion he won’t hint as to whether he would caucus with the Democrats and potentially be helping them keep control of the chamber. (Though he says he plans to cast a vote for Mr. Obama in November.)

This state will stay on our radar.

You can see the Senate Six on the NewsHour’s Vote 2012 Map Center and on air this election year.

Watch Christina debriefing about the project on the NewsHour.

Please subscribe to the Morning Line and follow Christina on Twitter. Join a Twitter chat with Christina Friday April 13 at 1 p.m. ET here.

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