Democrats worry that failure to convict Trump in Senate trial will lead to his reelection

The Hill:

Senate Democrats are bracing for President Trump to seize on the outcome of the upcoming impeachment trial as a source of momentum for his reelection bid.

With 67 votes needed to convict and remove Trump from office, the trial’s outcome is largely pre-baked since Republicans hold a 53-47 majority in the chamber. Democrats are worried that an acquittal will only embolden the president, and they feel powerless to prevent it.

“No matter what we do, the president is going to say he did nothing wrong,” said Sen. Chris Murphy (D-Conn.).

“We all know the president,” said Sen. Dick Durbin of Illinois, the No. 2 Senate Democrat. “If there are not 67 votes to convict in the Senate, he’ll claim that it was a witch hunt and that he was exonerated.”

Sen. Tim Kaine (D-Va.), when asked about the potential fallout from an acquittal, added: “I am worried about that, but I think this president feels unconstrained by anything already.”

Trump became only the third U.S. president to be impeached after the House passed two articles, largely along party lines, on Dec. 18. The first charged him with abuse of power in his dealings with Ukraine, and the second with obstructing Congress during its investigation of those actions.

Republicans are already pledging to give him an early election-year victory by acquitting him of the charges at the culmination of the Senate trial.

Sen. Christopher Coons (D-Del.) said in a recent “Meet the Press” interview on NBC that he was “gravely concerned” about Trump’s potential behavior between the end of the Senate trial and the 2020 election.

“If he is ultimately exonerated in the Senate, if the Senate Republican majority refuses to discipline him through impeachment, he will be unbounded,” Coons said, predicting that there would be “no restrictions” on Trump’s behavior.

Concern about the possible repercussions stemming from Trump being acquitted comes as the Senate is expected to start the trial in January, though the exact date is in limbo amid a stand-off between Democrats and Senate Majority Leader Mitch McConnell (R-Ky.) over the rules of the chamber’s proceedings.
...

So why didn't they oppose the impeachment in the Hosue and tell Pelosi et al that a trial will be counter-productive?  They had to be able to count the number of votes they would likely get in support of impeachment and know they would never get to 67 and probably would never get to 51. 

If the trial results in a victory for Trump the Democrats will get what they deserve, a sweeping defeat.  Ever since Trump was elected they have pushed one lie after another to try to get him removed from office, and impeachment was clearly a futile gesture on their part.