With their anticipated “no” votes on Judge Brett Kavanaugh’s confirmation to the Supreme Court, Sens. Jon Tester, D-Mont., and Claire McCaskill, D-Mo., voted against their constituents' wishes.

But chalk this up in their favor. Members of Congress are representatives either of their district or, in the case of senators, of their state. They are there to make their best decision on behalf of their constituents, not as ambassadors who should do no more and no less than their constituents tell them to do. Neither Tester nor McCaskill ever pretended to be anything other than the standard-issue Democratic partisans they are. And they voted accordingly.

The same cannot, however, be said of two other Democrats who announced their “no” votes this week. Sens. Heidi Heitkamp, D-N.D., and Joe Donnelly, D-Ind., sold themselves to the voters of their respective states as centrists and moderates. Now, when it matters and just weeks before they face voters on Election Day, they have chosen to please the Democrats’ left-wing donor base over their constituents.

North Dakotan and Hoosier voters should remember on Nov. 6 that both of these senators won their elections in 2012 based on false advertising. They lied, and neither one can be trusted now for anything they say.

In Heitkamp’s case, her decision appears to have been made out of desperation. Two recent public polls show her Republican challenger leading by double digits, which Republicans appear to believe is real, based on their decision to cancel ads in the state. Heitkamp risks having conventional party sources of fundraising dry up on her. Her best alternative is to turn to online fundraising from left-wing grassroots. That’s something a “no” vote on Kavanaugh might earn her.

Donnelly’s predicament is similar, although his danger of losing re-election is less acute, at least according to public polls. His conduct in this matter has, however, been especially two-faced and richly deserves electoral rebuke.

He originally announced, just hours before the Senate Judiciary Committee voted on the nomination on Sept. 28, that he would vote against Kavanaugh. He cited not the philosophy or temperament of the nominee, but the fact that there had been no FBI investigation into the allegations against him. “Sen. McConnell has refused to allow that FBI investigation,” he wrote. He added: “We have been unable to get all the information necessary regarding this nomination, despite my best efforts.”

But then, in a dramatic last-minute development, Sen. Jeff Flake, R-Ariz., leveraged his status as the deciding vote on the panel to demand just the FBI investigation that Donnelly claimed his vote hinged upon. Yet, when the FBI investigation came back with no corroboration of any allegations against Kavanaugh, Donnelly didn’t even bother to look at it before coming up with a new justification for voting against the nominee. This time, he cited anger that Kavanaugh displayed before the Judiciary Committee over the false and unsubstantiated accusations that had been launched against him.

Sen. Kamala Harris, D-Calif., the ultra-partisan and left-wing senator who made her 2020 presidential aspirations clear during the first round of Kavanaugh’s confirmation hearings, responded to both Heitkamp’s and Donnelly’s announcement by sending out a fundraising email to her list on behalf of each one.

The California leftist knows their votes suit her. There is no reason when those senators' constituents should, however, regard those votes as having anything to do with them. The leftists on Harris's email fundraising list are now sending cash to Indiana and North Dakota to rescue senators who represent her radical agenda better than they represent their own constituents. They are helping cement these senators’ loyalty toward Harris in her 2020 presidential bid.

Is that what Indiana and North Dakota want? It seems unlikely. Voters there should take note of this. They should judge Donnelly and Heitkamp by the company they keep.