A former U.S. ambassador to Canada believes Tuesday’s midterm elections will be decided by one key factor: character.

“I think Americans are voting on character: What is the country? Who are we? What are we all about?” said Bruce Heyman, who was the U.S. ambassador to Canada from 2014 to 2017, in an interview with BNN Bloomberg on Monday. 

“Americans have a big decision to make right now, and that decision is in light of this divisive way the president has led his administration, the hatred that he has applied to so many constituencies in America, that Americans need to come to the polls and decide what type of America they really want.”

All 435 House of Representative seats will be contested in Tuesday’s election in addition to 35 of the 100 U.S. Senate seats. The Republicans emerged from the 2016 presidential elections with control of both the House of Representatives and the Senate, and gubernatorial control of 33 of the 50 states. There are 36 gubernatorial races to be contested on Tuesday.

Heyman says a shift to a Democratic House would put some badly-needed checks and balances in place for the Trump administration.

“There are no checks and balances, because Republicans have just followed – hook, line, and sinker – the president’s diatribe and all of his actions. Nobody has gone against him,” Heyman said.

Heyman doesn’t think a Democratic-controlled Congress would nullify the USMCA agreement, adding that it “looks substantially like [the Trans-Pacific Partnership]” Trump so vehemently opposed. However, he said that the Democrats could look much closer at the president’s tariff policies, especially in regards to how it affects trade with Canada.

“The Constitution says foreign trade is owned by Congress,” he said. “Will Congress then hold his feet to the fire and say, ‘Hey, wait a minute. This makes no sense to go after Canada for national security reasons on steel and aluminum.’”  

And if the Republicans should hold the line in both houses? Then, Heyman said, Trump will “lean in” to his populist rhetoric and surround himself with a cabinet that is friendlier to his agenda.

“A number of cabinet members are rumoured to be going, potentially, after the midterms and I think he’ll get people who are more in agreement with his philosophies than anybody who is holding him to any kind of standard,” Heyman said

“He’ll be a more extreme version of himself. As bad as some people think it’s been the last couple years, I think he will lean in on that, because he’ll have the House and the Senate.”