Senate Democrats are becoming concerned about House speaker Nancy Pelosi's continued refusal to submit the articles of impeachment to the Senate so the matter can be tried there.  Democrats had been hoping, after a rushed investigation in the House (one so hurried that Democrats never fully developed their so-called case), that they could force the Senate to give them an opportunity to introduce more evidence in that chamber.

Senator Mitch McConnell (R-Ky.), however, has refused to engage in any deal-making with the Democrats.  Instead, he insists that the Senate majority — meaning the Republicans — will set the terms for Senate impeachment proceedings, just as the House majority — meaning the Democrats — set the terms for House proceedings.

Politico reports that Senator Dianne Feinstein (D-Calif.) is grumbling that Pelosi's delay in order to get concessions has instead managed to make the Democrats' case against President Trump look weak:

"The longer it goes on the less urgent it becomes," said Sen. Dianne Feinstein (D-Calif.). "So if it's serious and urgent, send them over. If it isn't, don't send it over."

Feinstein is not the only one expressing concern.  Senator Joe Manchin (D-W.Va.), who often tries to present a more conservative face to his constituents even as he usually votes a straight party line, is also getting concerned that Pelosi's delay is putting the lie to the House Democrats' contention that Trump engaged in such major malfeasance he had to be removed from office immediately:

Several other Senate Democrats also showed their impatience with the Democratic leaders' current strategy. Sen. Joe Manchin (D-W.Va.) said Wednesday morning that Democrats "should move on" and turn the articles to the Senate and Sen. Jon Tester (D-Mont.) said he's "ready" for the trial to start.

"We need to get folks to testify and we need more information ... but nonetheless I'm ready," Tester said. "I don't know what leverage we have. It looks like the cake is already baked."

"I respect the fact that she is concerned about the fact about whether or not there will be a fair trial. But I do think it is time to get on with it," said Sen. Chris Coons (D-Del.).

While the Democrat senators seem to be getting edgy, House Democrats are still united behind Speaker Pelosi, although some of them are getting restless, too:

"Realistically there is a timeline, there's a limit. The American people are going to want this to happen sooner rather than later," said Rep. John Yarmuth (D-Ky.). "It did give us a couple of weeks, three weeks, to just keep pounding home 'what are they trying to hide?' But we can't keep that drumbeat up forever."

Even if Pelosi had a good strategy when she decided to try to force a negotiation, it's likely that events concerning Iran, including Trump's swift, decisive handling of Iran's aggression, are causing most people to consider the impeachment an irritating distraction, not a compelling necessity.  Most are reasoning, as Feinstein did, that Pelosi's sudden lack of urgency signals that the House proceedings were more about theater than substance.