Republicans are strong favorites to retake the Senate majority this fall, according to The Post's new Election Lab model. (Read more about it here.)

According to the model, which was built for The Post by political scientist and Monkey Cage blog author John Sides, Republicans have an 82 percent chance of claiming the six seats they need to move back into the majority. Explains Sides:

The main problem for Democrats is that it’s a midterm year — and the president’s party almost always loses seats in the midterm. Moreover, conditions make it difficult for Democrats to overcome this tendency: The economy is not growing that strongly and, partly as a consequence, President Obama is not that popular. Moreover, as many have noted, many seats that the Democrats must defend this year are in Republican-leaning states.

Given these conditions, the political science literature suggests that quality Republican candidates should emerge. This is because quality candidates are strategic: They tend to run when their chances of winning are higher. Thus, many Republican candidates have significant political experience in state legislatures, the U.S. House of Representatives, and in other offices. (In states where primaries haven’t taken place, we assume that the eventual party nominees will have an average experience level like that of nominees in similar races in the past.)

Of the two Republican seats seen as potential pickups for Democrats, neither look promising. Republicans have a 94.37 percent chance of holding onto the open Georgia seat and upwards of a 97 percent chance of keeping the Kentucky seat. On the other hand, there are currently eight Democratic-held seats where the Election Lab gives Republicans a better than 50 percent chance of winning. In order, they are:

1. South Dakota (99.14 percent of GOP takeover)

2. West Virginia (94.58 percent)

3. Montana (73.05 percent)

4. Louisiana (72.48 percent)

5. Iowa (64.97 percent)

6. Michigan (57.7 percent)

7. Arkansas (55.94 percent)

8. Alaska (50.49 percent)

The two outliers on that list, at least at first glance, appear to be Michigan and Iowa — both of which look better in the model for Republicans than conventional wisdom dictates. Ben Highton, a political science professor at UC-Davis, wrote last month about the model's projections in each state.

• Iowa: "Here, if we had to guess, we'd say the model is overly bullish for the Republicans. The reason is that the Democrats have a good candidate in Rep. Bruce Braley, and the Republicans may not be able to recruit a top-tier candidate.  But our model does not have this information about what’s going on with the Republicans in Iowa.  It assumes that the Republicans will have a 'typical' candidate in terms of quality for an open-seat race, which does not appear very likely right now."

• Michigan: "While the Democratic nominee will likely be Rep. Gary Peters, the Republicans also have an apparently strong candidate with former secretary of state Terri Lynn Land.  In combination with the seat being open and the state being only modestly more Democratic in presidential voting than the nation overall, our model currently gives the Republicans a 58 percent chance of winning this seat."

It's also worth remembering that the model gets better as more information — on candidate quality, fundraising, overall national political mood, etc. — becomes available. So, the Election Lab model will be better in a month than it is today. And better in two months than that.

Still, while the model might be somewhat bullish on Republican prospects at the moment, it is in keeping with the general sense that the GOP is quite well positioned — both in terms of the seats up and the number of Democratic seats in jeopardy — to retake the majority.