First, the Senate. The view here—based on state polls, our own reporting and national trends—is that Republicans will easily take Democratic seats in Montana, South Dakota and West Virginia. Republicans will also pick up Arkansas, Alaska, Colorado and Iowa. The result in Alaska, however, may not be known for days, as the race remains tight and many in the sprawling, lightly populated state vote by absentee ballots that may not be counted for weeks.
Kansas remains difficult to call, but we give it to independent Greg Orman given his persistent narrow poll lead, knocking Republicans back one seat. Democrats Kay Hagan in North Carolina and Jeanne Shaheen in New Hampshire will narrowly hold on.
The above scenario would put Republicans right at the six-seat gain they need to control the Senate. But they may not be there as of Wednesday morning if Alaska remains uncalled. And there will be two races still hanging fire.
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Louisiana is going to a Dec. 6 runoff barring some big surprise. And if Republican Bill Cassidy wins the runoff, as is likely, GOP control of the Senate will be cemented on Dec. 7. However, we also think the Georgia Senate race is going to a Jan. 6 runoff. So if incumbent Sen. Mary Landrieu manages to hold on in Louisiana, Democrats could have a chance to hang on to the Senate if they can push Michelle Nunn to victory in January.
Still, the call here is that Republicans finish plus six in the Senate after Tuesday's vote and then lock down the majority on Dec. 6 in Louisiana.
In the House, there appears to be no big national wave that would deliver massive gains to Republicans. Polls show Americans very unhappy with President Barack Obama and the state of the economy. But they also show little enthusiasm for Republicans. And the GOP has done absolutely nothing to create a unified national message. If Republicans add much bigger numbers in the House it will be because of major trends undetected by current polling.
Democrats will probably get their best headlines out of governor's races where they will likely retake Pennsylvania and possibly Florida, among others. Republicans, meanwhile, are likely to take over the governorship in Arkansas and have decent chances in Colorado, Connecticut, Illinois, Massachusetts and Rhode Island, where Obama will campaign on Friday.
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Barring a massive surprise, Republicans will be the clear winners on Election Night and will hand Obama the worst combined midterm results for any two-term incumbent president since Democrat Harry S. Truman.
Still, Democrats will be able to shrug off the expected losses within a few days because 2016 looks much brighter for them. Barring unforeseen events, they have a presidential nominee in waiting in Hillary Clinton, saving them a costly and potentially damaging primary battle. That could certainly change with the entry of Sen. Elizabeth Warren, D-Mass., or some other candidate to Clinton's left. And Clinton could shock the entire world and decide not to run. But all of that seems unlikely.
Republicans, meanwhile, could field a dozen or so presidential candidates all trying to destroy each other to claim the party's 2016 nomination. And the Senate script flips in the next election with Republicans defending marginal seats won in the tea party wave of 2010. As Burgess Everett reports Friday in Politico, six first-term Republicans face re-election in states Obama won twice: Mark Kirk of Illinois, Pat Toomey of Pennsylvania, Ron Johnson of Wisconsin, Rob Portman of Ohio, Kelly Ayotte of New Hampshire and Marco Rubio of Florida.
A strong showing by Clinton at the top of the ticket could sweep some or all of those freshman Republicans out of office, tipping the Senate back to Democrats after just two years. Taking the House back in 2016 will be far harder for Democrats, however, meaning if Clinton wins, she will face a Capitol Hill much like the one Obama dealt with beginning in 2011. The question then will be how she deals with it. But that's well down the road, for now Republicans should look forward to a good night Tuesday night.
—Ben White is Politico's chief economic correspondent and a CNBC contributor. He also authors the daily tip sheet Politico Morning Money [politico.com/morningmoney]. Follow him on Twitter @morningmoneyben.