Three weeks after the Democratic National Convention, we see little indication that the lead President Barack Obama took after it has faded. Obama is leading Mitt Romney by about four percentage points nationally, according to an average of national horserace surveys, and his edge has trickled down to the swing states.

So with 40 days to go, we’re moving several toss-up states in the president’s direction. Our changes push Obama over the magic 270 mark, but we are not calling the race. First, the debates are yet to come. There is at least the possibility that, if Romney fares particularly well or Obama does poorly, the drift of this contest could change. Second, other events — international (a crisis) or domestic (dramatically poor economic numbers) — could theoretically occur to re-write the narrative of the race. So caution is always in order with almost six weeks to go, yet President Obama clearly leads at the moment.

Chart 1: Crystal Ball ratings changes, presidential race







Map 1: Updated Crystal Ball electoral map

These rating changes move five of our eight toss-up states into Obama’s column, giving him 290 electoral votes to Mitt Romney’s 206, with Colorado, Florida and New Hampshire as toss-ups (42 votes). Obviously, Romney needs to turn some of the blue on this map to red, or this race will be over. And much of Obama’s territory is unavailable to him: the states won by both Al Gore in 2000 and John Kerry in 2004 add up to 242 electoral votes on this map. Other than Wisconsin, Romney appears to have little chance of winning any of the other Gore/Kerry states. And the Badger State, despite Paul Ryan’s presence on the ticket, appears to be moving away from him as well.

Provided Romney wins the three toss-ups, he will then need to pry another 22 electoral votes from Obama. And that will be difficult: Of all the states at least leaning toward Obama in our ratings, the president’s smallest polling lead, based on the RealClearPolitics average from mid-day on Wednesday, was four points in Iowa.

Chart 2: RealClearPolitics polling averages in competitive presidential states







Our rating changes are based on polling, reporting and our own judgments about the individual races. They are not set in stone, and we wouldn’t be surprised if we switched some states in October or early November. Please keep that in mind. Politics is a dynamic, not a static, business.

Of course, if the current polls showing a decisive Obama victory turn out to be correct — and we have our doubts — then Democrats will win a lot more than we’re projecting in the Electoral College, the Senate, and the House.

In Senate battle, Democrats go with the flow…

As President Obama has grabbed and maintained an edge both nationally and in many crucial swing states, Democratic Senate candidates made their moves in a number of key swing states where Obama appears to be leading. While Republicans have a few bright spots too, the overall movement in the Senate is unmistakably toward the Democrats.

Chart 3: Crystal Ball Senate rating changes







Map 2: Updated Crystal Ball Senate map

In Florida and Ohio, Sens. Bill Nelson (D) and Sherrod Brown (D) are not only favored, but we believe that Republicans and their allies ultimately might have better places to spend their money. Given that both should ultimately run ahead of Obama — especially Nelson — these races may be out of range for the GOP, although we are keeping both in the leans Democratic category for now. The same thing goes for New Mexico, where Republicans have apparently already abandoned their candidate, ex-Rep. Heather Wilson. We’re upgrading Rep. Martin Heinrich’s (D) chances to likely Democratic, which matches our rating of the state in the presidential race. The situation is quite similar in Hawaii, where we now see Rep. Mazie Hirono (D) as a stronger favorite against ex-Gov. Linda Lingle (R). In a state where Obama might again get 70% or more of the vote, Hirono is now likely to win the seat. By the way, the Crystal Ball has consistently rated Heinrich and Hirono the favorites in their races. Some trends have been apparent for months.

In another state Obama will win by a mile — Massachusetts — consumer advocate Elizabeth Warren is making a charge against Sen. Scott Brown (R-MA). The Bay State race is a classic test of candidate skills (Brown, a natural, is far better than Warren) versus coattails (which strongly benefit Warren, since Romney will be lucky to muster 40% of the vote in the state he governed from 2003 to 2007). In the end, it’s better to be a Democrat in Massachusetts, but Brown’s strength as a candidate means we’re not quite ready to close down the contest.

In Virginia, we’ve long believed that the race between ex-Gov. Tim Kaine (D) and ex-Sen. George Allen (R) would mirror the presidential contest, and that’s now reflected in the polling: Obama is up 4.5 percentage points in Virginia, and Kaine is up 4.4 points, both according to the RealClearPolitics average. We’re also coming to believe that a small but noticeable crossover vote for Kaine is surfacing, which might allow him to win even if Romney comes back in the Old Dominion to win by a point or two. All of this tells us that Virginia’s Senate race leans Democratic, at least at this juncture.

Potential Obama wins in Nevada and Wisconsin could also hurt Sen. Dean Heller (R) and ex-Gov. Tommy Thompson (R). Our Nevada sources believe Heller retains a slight edge over the challenger, Rep. Shelley Berkley, but Berkley may be the Western Warren — a not-so-strong candidate that Obama and his Democratic turnout operation might carry over the finish line. Thompson, meanwhile, is getting crushed on the airwaves by Rep. Tammy Baldwin (D), who has surprisingly taken the lead in their race. Nevada and Wisconsin are now Senate toss-ups. Either or both could be roller coaster races, with the lead trading hands in the stretch run.

The one Senate candidate on the Democratic side who seems unable to break through despite Obama’s improving numbers is Rep. Chris Murphy (D-CT), who is locked in a duel with Republican Linda McMahon. McMahon has run a much better race than she did two years ago, and Murphy has been unimpressive and has had a number of nagging problems, including attacks over missing mortgage and rent payments. It seems almost inconceivable that McMahon — hardly a perfect candidate herself — could win this race in the Nutmeg State in a presidential year, with President Obama easily capturing the state. And yet, here we are: The Connecticut Senate race is now a toss-up.

… and run against the wind

Among the truly competitive Senate races, there are contests that are being fought in good Obama states, and there are ones that are not.

Indiana and North Dakota should both go for Mitt Romney by substantial margins, even though Obama won the Hoosier State in 2008 (he is making no effort to win it this time). And yet these quiet presidential states have white hot Senate contests. Former state Attorney General Heidi Heitkamp (D-ND) and Rep. Joe Donnelly (D-IN) seem to be doing a fine job of holding back the red tide in their respective states, and they have been aided by weak Republican opponents, Rep. Rick Berg (R-ND) and Treasurer Richard Mourdock (R-IN). As Crystal Ball readers know, we have noted the potential competitiveness of these races for months, but we have resisted moving them to the toss-up category. No longer. We know that both sides are putting money into these states, and there is no recent, reliable public polling in either contest. Ultimately, we believe the Republican candidates have a clearer path to a plurality in these races than do the Democrats. But there just isn’t enough information to justify rating either Indiana or North Dakota as leaning Republican anymore. In Mourdock’s case, he might get coattails not so much from Romney, but from Rep. Mike Pence (R), who appears to be comfortably ahead in his campaign to succeed the retiring and popular Gov. Mitch Daniels (R).

Meanwhile, there are some bright spots for Republicans in our rating changes beyond Connecticut. Montana remains very close, but we think that Rep. Denny Rehberg (R) is now a tiny favorite to unseat Sen. Jon Tester (D), even if it’s only by a few thousand (or hundred) votes. A Mason-Dixon poll showing Rehberg up three points over Tester helped reinforce our thinking in this race; for what it’s worth, Rehberg has led 10 of 13 polls taken in this race since the end of 2010. That’s not really saying much, but Tester might be the Democratic version of Scott Brown this year — a personally popular politician done in by the performance of his presidential ballot-mate.

We also now understand why Republicans, over the past several weeks, have been making so much noise about the Maine Senate race. The polls in that three-way race have tightened enough that independent former Gov. Angus King, who we believe would caucus with the Democrats, is not quite as imposing a front-runner anymore. The race now leans Democratic/independent, but national Democrats have to be worried that this race will be a repeat of 2010’s gubernatorial election, where a Democrat and an independent split the vote and permitted Tea Party Republican Paul LePage to become governor. King is competing not only with Republican Charlie Summers, but also Democrat Cynthia Dill. Democrats are determined not to let this opportunity — created by the retirement of Sen. Olympia Snowe (R) — slip away. It may be that the Democratic Senatorial Campaign Committee will start to explicitly support King, or claim that a “vote for Dill is a vote for Romney and Summers.”

King has something in common with Wisconsin’s Thompson: the former governors last won an election way back in 1998, nearly a decade and a half ago. Has the game changed too much for them to win again? We’ll find out soon enough.

Republicans probably wouldn’t be targeting Maine if it weren’t for Missouri, where Rep. Todd Akin’s (R) struggles are well-documented. Sen. Claire McCaskill (D), like Tester, should be an underdog, but thanks to Akin’s mistakes — and his failure to leave the race as a deadline passed Tuesday — she is now a favorite to win a second term. Never did the GOP imagine that the extremely vulnerable McCaskill, almost a pushover to lose, might be elected virtually by default. We wonder what the abstention rate will be in this contest. Or maybe the Libertarian on the ballot is the one who stands to gain a few percentage points.

The Senate’s bottom line

After these 11 rating changes, and assuming that the 67 senators not up for reelection this year return for the next Congress, we’re left with a 49-45 Democratic lead in the Senate, with six toss-ups: Connecticut, Indiana, Massachusetts, Nevada, North Dakota and Wisconsin. Republicans need to sweep all six to win the Senate outright. As of today, we would project that Democrats would win two of the six toss-ups, good enough for a 51-49 edge that would keep Sen. Harry Reid (D-NV) majority leader despite a net loss of two seats.

In the House, a small Democratic uptick

While we substantially re-worked our House ratings last week, we imagine we’ll be tweaking them all the way up until Election Day. So there are a few changes from last week.

Chart 4: Crystal Ball House rating changes







Rep. David Rivera (R, FL-26), whose legal troubles might make for a good Coen brothers movie script some day, might return to the House. But challenger Joe Garcia, who is running for this seat for the third time in a row, has released several recent polls showing him ahead of Rivera. This race now leans Democratic. Going from the shores of the Gulf of Mexico to the shores of the Great Lakes, Rep. Dan Benishek’s (R, MI-1) rematch with ex-state Rep. Gary McDowell (D) in Michigan’s Upper Peninsula is now a toss-up; neither of these candidates have Rivera-esque problems, but both have provided ammunition to the other side, setting up a “Mediscare” battle on both sides. The polls we’ve seen indicate a very close race.

Meanwhile, Rep. Chris Gibson (R, NY-19), who represents a district south of Albany, had to be pleased with a Siena Poll that showed him up 16 points over challenger and former prosecutor Julian Schreibman. We’ve long thought that Gibson was slightly better-positioned to return to Congress than fellow freshman Rep. Nan Hayworth (R, NY-18), who represents a district closer to New York City and south of Gibson’s district. We’re also keeping a close eye on NV-4; Democrats should ultimately prevail, but the Republican candidate is Danny Tarkanian, who is blessed with a celebrity last name (his father, Jerry, was a famous basketball coach at the University of Nevada, Las Vegas). This race is leans Democratic, for now.

With these changes, and reassessments of how some of our toss-up races might fall on Election Day, we’re returning to a projection of Democrats +6 seats, or a 236-199 Republican-controlled House. That’s up two for the Democrats from last week.

Our full list of House ratings is available here.