The midterm elections are just over nine months away. What will Democrats run on? What will Republicans run on?

One hint came at a Houston-area Trump rally Saturday night. “If I run and if I win,” the former guy said, referring to 2024, “we will treat those people from January 6th fairly.” He then added, “and if it requires pardons, we will give them pardons, because they are being treated so unfairly.”

Trump went on to demand “the biggest protest we have ever had” if federal prosecutors in Washington or in New York and Atlanta, where cases against him are moving forward, “do anything wrong or illegal”. He then called the federal prosecutors “vicious, horrible people” who are “not after me, they’re after you”.

Trump’s hint of pardons for those who attacked the Capitol could affect the criminal prosecution of hundreds now facing conspiracy, obstruction and assault charges, which carry sentences that could put them away for years. If they think Trump will pardon them, they might be less willing to negotiate with prosecutors and accept plea deals.

His comments could also be interpreted as a call for violence if various legal cases against him lead to indictments.

But if Trump keeps at it – and of course he will – he’ll help the Democrats in the upcoming midterm elections by reminding the public of the attempted coup he and his Republican co-conspirators tried to pull off between the 2020 election and January 6. That would make the midterm election less of a referendum on Biden than on the Republican party. (Don’t get me wrong. I think Biden is doing a good job, given the hand he was dealt. But Republicans are doing an even better job battering him – as his sinking poll numbers show.)

Last week, Newt Gingrich, who served as House speaker from 1995 to 1999, suggested that members of the House select committee investigating the January 6 attack on the Capitol should face jail time if the Republican party returns to power. “The wolves are gonna find out that they’re now sheep, and they’re the ones who – in fact, I think – face a real risk of jail for the kind of laws they’re breaking,” Gingrich said on Fox News.

Gingrich’s remark prompted Representative Liz Cheney, Wyoming Republican and vice-chair of the select committee, to respond: “A former speaker of the House is threatening jail time for members of Congress who are investigating the violent January 6 attack on our Capitol and our constitution. This is what it looks like when the rule of law unravels.”

Trump and Gingrich are complicating the midterm elections prospects for all Republicans running or seeking reelection nine months from now.

Many Republican leaders believe they don’t need to offer the public any agenda for the midterms because of widespread frustration with Biden and the Democrats. Senate minority leader Mitch McConnell, recently asked what the Republican party’s agenda would be if it recaptured Congress, quipped “I’ll let you know when we take it back.”

But if Republicans fail to offer an agenda, the Republican party’s midterm message is even more likely to be defined by Trump and Trumpers like Gingrich: the big lie that the 2020 election was stolen along with promises to pardon the January 6 defendants, jail members of the select committee investigating the attack on the Capitol, and other bonkers claims and promises.

This would spell trouble for the GOP, because most Americans don’t believe the big lie and remain appalled by the attack on the Capitol.

House minority leader Kevin McCarthy (who phoned Trump during the attack on the Capitol but refuses to cooperate with the House’s January 6 committee investigation) will have a central role in defining the Republican message for the midterms. And whom has McCarthy been consulting with? None other than Newt Gingrich. The two have been friends for years and McCarthy’s chief of staff in his leadership office, Dan Meyer, served in the same role for Gingrich when he was the speaker.

McCarthy knows Gingrich is a master huckster. After all, in 1994 Gingrich delivered a House majority for the Republicans for the first time in 40 years by promising a “contract with America” that amounted to little more than trickle-down economics and state’s rights.

But like most hucksters, Gingrich suffered a spectacular fall. In 1997 House members overwhelmingly voted to reprimand him for flouting federal tax laws and misleading congressional investigators about it – making him the first speaker panned for unethical behavior. The disgraced leader, who admitted to the ethical lapse as part of a deal to quash inquiries into other suspect activities, also had to pay a historic $300,000 penalty. Then, following a surprise loss of Republican House seats in the 1998 midterm election, Gingrich stepped down as speaker. He resigned from Congress in January 1999 and hasn’t held elected office since.

I’ve talked with Gingrich several times since then. I always come away with the impression of a military general in an age where bombast and explosive ideas are more potent than bombs. Since he lost the House, Gingrich has spent most of his time and energy trying to persuade other Republicans that he alone possesses the strategy and the ideas entitling him to be the new general of the Republican right.

Gingrich has no scruples, which is why he has allied himself with Trump and Trump’s big lie – appearing regularly on Fox News to say the 2020 election was rigged and mouth off other Trumpish absurdities (such as last week’s claim that members of the House select committee should be jailed).

Gingrich likes to think of himself as a revolutionary force, but he behaves more like a naughty boy. When he was Speaker, his House office was adorned with figurines of dinosaurs, as you might find in the bedrooms of little boys who dream of becoming huge and powerful. Gingrich can be mean, but his meanness is that of a nasty kid rather than a tyrant. And like all nasty kids, inside is an insecure little fellow who desperately wants attention.

Still, as of now, the best hope for Democrats in the midterms lies with Trump, Gingrich and others who loudly and repeatedly remind the public how utterly contemptible the Republican party has become.

• Robert Reich, a former US secretary of labor, is professor of public policy at the University of California at Berkeley and the author of Saving Capitalism: For the Many, Not the Few and The Common Good. His new book, The System: Who Rigged It, How We Fix It, is out now. He is a Guardian US columnist. His newsletter is at robertreich.substack.com