Assuming the FBI investigation of Judge Brett Kavanaugh doesn’t uncover some startling new information, the Senate is likely to confirm him to the Supreme Court and the political effects on the midterms could go in two different directions.

Democratic lawmakers will complain, of course, that the inquiry wasn’t thorough enough, that Kavanaugh lacks a judicial temperament, that he is too partisan to sit on the land’s highest court, and that he wasn’t completely honest with the Senate Judiciary Committee about his drinking.

Still, if all 51 Republican senators are looking for a way to confirm Kavanaugh, Democrats are powerless to derail the nomination.

Open House?

The impact on the fight for the House is likely to be minimal.

There probably will be about a month between Kavanaugh’s confirmation and Nov. 6, which should give many voters an opportunity to refocus on other issues, be they health care, immigration or President Donald Trump’s performance.

Of course, in states with early/absentee/mail voting, the confirmation fight will still be on some people’s minds. But the Kavanaugh fight has not redrawn the electoral battle lines during the final six weeks of the election.

Democrats were already energized when Kavanaugh was nominated, and Trump’s strongest supporters have remained loyal to him no matter what he says or does.

Republican primary turnout was good, though it didn’t match — and isn’t likely to match — Democratic turnout or enthusiasm.

Recently, some pollsters have argued that heightened Republican enthusiasm could eat into the Democrats’ expected turnout advantage in November. But if and when Kavanaugh is confirmed, that event will give the GOP “control” of the White House, the Senate, the House of Representatives and the Supreme Court, and that will remove some of the urgency about the midterms for Republican voters.

Democrats, on the other hand, will see the midterms as their only opportunity to check Trump and his party. During the month between Kavanaugh’s confirmation and Election Day, the president is likely to return to his combative mode.

He will interject himself back into every House race, as he has been for months, thereby reminding voters that the midterms are about him.

The 2018 election’s crucial swing group — college-educated whites/white women — will be at least as energized after the Kavanaugh fight as they were before his nomination.

Polls have shown for months that swing voters (particularly women) have been preparing to send a loud message to Trump and the Republican Party, and the accusations about Kavanaugh will only further motivate college-educated women who live in the suburbs.

Both national polls and district surveys conducted by the media and by campaigns, as well as campaign spending decisions by the parties and PACs, show at least a modest Democratic wave developing.

According to national media reports, influential Republican political action committees have pulled out of Virginia’s 10th District (Barbara Comstock), Colorado’s 6th District (Mike Coffman) and Michigan’s 8th District (Mike Bishop).

Those districts are telling, since Coffman and Comstock were able to win even while Democratic presidential nominees were carrying their districts, and Bishop represents a district carried by both Trump in 2016 and Mitt Romney in 2012.

All three are politically competitive suburban districts. District-level polling also shows significant Republican problems — again, primarily in the suburbs — in New Jersey, Iowa, North Carolina, Pennsylvania and California, and Republican funds are now flowing into districts not initially regarded as even competitive in the past.

Democratic gains of at least 30-35 seats currently appear likely, and there is little reason to believe that the Kavanaugh confirmation fight will change that outcome.

Indeed, if it does have any impact, it will probably be to the Democrats’ advantage.

Meanwhile, in the Senate

The Supreme Court battle could have quite a different effect on the race for the Senate. Instead of college-educated, suburban whites being the key swing demographic group, self-identified Republicans, rural voters and Trump voters are crucial in these contests.

Democratic incumbents in North Dakota and West Virginia certainly need to win some of those voters to have any chance of surviving (as do Democratic incumbents in three or four other states).

So Democratic senators in difficult races have a complicated calculation to make.

On one hand, if Republicans are going to confirm Kavanaugh with 50 or 51 votes anyway, endangered Democratic senators could boost their chances by casting meaningless votes in favor of the nominee — thus proving their political independence to swing voters and Republican voters in pro-Trump states such as North Dakota, West Virginia and Indiana.

On the other hand, the intensity of the Kavanaugh fight makes it more difficult for Sens. Heidi Heitkamp, Joe Manchin III and Joe Donnelly to support confirmation because Democratic base voters are so outraged at Trump and Senate Republicans.

Voting for Kavanaugh — even if it has no impact on his confirmation — could anger and alienate those voters, which could well be fatal to the Democratic incumbents.

Of course, Democratic senators such as Donnelly now have new arguments to explain a vote against confirmation — the alleged unfairness of the process, questionable statements from Kavanaugh and the unanswered questions raised during the testimony of his accuser, Christine Blasey Ford.

While Democrats would love to kill the Kavanaugh nomination, dragging out the process to fill the court’s vacancy would only add to the concerns of Democratic senators running in heavily pro-Trump states by elevating the importance of partisanship, ideology and the Supreme Court.

That is less of a problem for Democrats in the House than it is for this cycle’s Senate class. Given the unexpected twists and turns of our politics these days — and of the Kavanaugh confirmation process — it’s probably wise not to rule out a few more twists and turns before November.

This column originally appeared in Roll Call on October 2, 2018.