President Trump with Sen. Dean Heller (R-Nev.) at the White House in July 2017. Heller is up for reelection in November. (Jabin Botsford/The Washington Post)
Opinion writer

Do not get me wrong, I am not predicting the Senate will flip to a Democratic majority. However, I am not alone in seeing increasing prospects for that outcome — or for Democrats to at least maintain the current 49-51 split during an election cycle in which they must defend a disproportionate number of red states (e.g., Montana, North Dakota, Indiana) and purple states that President Trump won in 2016 (e.g., Pennsylvania, Ohio).

Charlie Cook of the Cook Political Report writes:

I am beginning to wonder whether my estimate of a 25-35 percent chance of the Senate flipping may be a little low. Just less than seven months out, this wave looks pretty formidable.

So what could turn this around? What could build Republican intensity and turnout to something comparable to what seems to be forming for Democrats? There seems to be three possibilities: guns, impeachment, and a Supreme Court vacancy.

Cook surmises the gun issue favors Democrats, but that the last two (preventing impeachment and a possible Supreme Court opening) favor Republicans. But from our vantage point, all three could favor Democrats. Anti-gun forces are energized; a desire to hold the president accountable (and if a damning special counsel’s report comes out, even impeachment) favors Democrats; and the opportunity to do a reverse Merrick Garland (preventing a Supreme Court seat from being filled) would motivate Democrats as well.

Moreover, two other grass-roots movements play to Democrats’ strengths: the #MeToo movement and “dreamers.” Each could mobilize specific Democratic interest groups as well as suburban, college-educated and younger voters who view Trump and the Republican Party as throwbacks to the 1950s, when it comes to the treatment of women and nonwhites.

The issue of sexual assault and abuse gets a jolt each time we learn about another alleged mistress or lawsuit. The “mad as hell and not going to take it anymore” sentiment that many women feel is reflected in the shift of white women voters toward Democrats, a phenomenon we saw during elections in 2017, and during Conor Lamb’s March victory in special congressional election in Pennsylvania. (By the way, the Senate has yet to consider the bill passed by the House setting out news procedures for sexual harassment complaints.)

The dreamers issue, no matter how hard Trump tries, will be a motivating issue for Hispanics and Democrats who understand it was the president who rescinded the Deferred Action for Childhood Arrivals program, and that it was also Trump who nixed a compromise bill to protect the dreamers by threatening a veto. Support for dreamers extends to nearly every cross-section in the electorate — even among Republicans. DACA certainly will come up in Florida, Texas, Nevada and Arizona Senate races. (If Democrats can get their act together to register plenty of new millennial voters and Hispanics, the Senate race in Texas might become competitive, though incumbent Republican Ted Cruz is still the favorite.)

Finally, one really needs to drill down on a state-by-state basis with regard to both Senate and House races. National polling on congressional preference can give a general sense of races, but close-up, a number of states look even worse for Republicans. In New Jersey, where Sen. Robert Menendez (D-N.J.) is looking to keep his seat after a corruption trial, and where multiple House seats are up for grabs, the numbers overwhelmingly favor Democrats. Likewise, take Wisconsin, which Trump won in 2016. The president’s net approval rating there (-12 points), and a recent Democratic victory in a state supreme court race indicate that incumbent Sen. Tammy Baldwin (D) has a good chance to hold on to her seat.

As we said, the Senate numbers still favor the Republicans. But between guns, #MeToo, the dreamers and state-level polling, one shouldn’t bet the farm that Republicans hold the Senate.