WASHINGTON — Anxious to see the results of all those Russia investigations going on in Congress and in special counsel Robert Mueller's office? Well, take a deep breath. It's likely to be awhile.

The constant stream of news about witnesses, subpoenas and closed-door testimony may make it feel like the Russia probes have been going on forever, but Mueller has only been on the job about four and a half months and the three congressional committees conducting inquiries didn't really start digging in until spring.

That's not long when you consider that the Watergate investigation of Richard Nixon took about 20 months — considered relatively fast — and the Whitewater investigation of Bill Clinton, which morphed into the Monica Lewinsky investigation, spanned about five years.

"The public and the press have always been impatient about how quickly these types of investigations are moving, but they have gotten more so," said Charles Tiefer, a professor at the University of Baltimore School of Law and the special deputy chief counsel for the House Iran-Contra Committee's investigation of the Reagan administration. "The 24-hour news cycle means that speculation outruns the actual investigation and demands responses."

Tiefer estimated that it could take Congress until spring and Mueller about a year to begin to show initial results, such as preliminary reports from the committees or the first round of indictments from the special counsel.

The special counsel, the Senate and House Intelligence committees and the Senate Judiciary Committee are all investigating Russian interference in the 2016 presidential election and possible collusion between the Trump campaign and Russian officials.

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"They have difficult obstacles to overcome," Tiefer said. Among them: convincing reluctant witnesses to cooperate, obtaining scores of documents from both inside the U.S. and Russia, and trying to persuade one of the targets to break ranks and become a witness for the prosecution.

Attorney Richard Ben-Veniste, who served as an assistant special prosecutor in the office of the Watergate Special Prosecution Force and chief minority counsel to the Senate Whitewater Committee, said the Russia probe and Watergate are "roughly comparable in terms of the complexity."

"Judged by other investigations and given the breadth of this one, I don't think the public should be too expectant, but rather appreciate the complexity ... and scope of the areas that both Mueller and congressional investigators are charged with looking into," Ben-Veniste said.

Bruce Udolf, a criminal defense attorney in Florida who served as an associate independent counsel during the Whitewater investigation, said he believes Mueller is "moving at lightning speed" in putting together a team of investigators and questioning witnesses.

Mueller is dealing with complicated issues of money laundering and obstruction of justice, with witnesses and evidence scattered across the globe, Udolf said.

"Of necessity, it's going to take a very long time," he said. "I would be surprised if it was completed in less than a year. But it sounds like he's making a lot of progress. I'm sure his team is working around the clock."

It's more important that an investigation be thorough than fast, Udolf said.

"You turn over one stone, and it leads you down another path," he said. "And you're dealing with people who are trying to prevent you from doing your job, which is getting to the truth."

Lanny Davis, an attorney who specializes in crisis management and a former spokesman and special counsel for ex-president Bill Clinton, said no one wants these kinds of investigations over faster than an innocent target.

Davis said the best thing an attorney with an innocent client can do is cooperate fully with prosecutors and congressional investigators to help speed up the process.

"You have to do the opposite of what you're taught to do as a private lawyer, which is to resist and drag things out," Davis said. "In this situation, if investigators don't ask for something, you offer it to them anyway. You drown them with paper, facts, and transparency."

However, it can sometimes be difficult for attorneys to convince their clients that this counter-intuitive strategy is the best way to go. Often, Davis said, a client's initial reaction will be: "What, are you kidding me? Whose side are you on?"

"You have to convince them that the way to end the investigation is to help investigators, not stop them," he said.

However, when an attorney has a client who may be guilty, that strategy must change, Davis said. He said the response still can't be "resist, resist, resist" because that could end up getting a client charged with obstruction of justice.

"You still have to cooperate," he said. "But you don't open the kimono and say come on in."

Former senator Bob Graham, a Florida Democrat who served as chairman of the Senate Intelligence Committee from 2001 to 2003, is urging Congress to complete its investigations well before the midterm elections in November 2018.

"I think there needs to be a real sense of urgency by Congress because of the possible consequences to the country," Graham said. "There could be another round of Russian meddling. They need to get to the bottom of what happened and prevent it from happening again."

Rep. Adam Schiff of California, the senior Democrat on the House Intelligence Committee, said in a recent interview that "it's still fairly early in the investigation."

"We're making progress, but it's very hard to give a timeline," he said.

Ben-Veniste said he has faith in both Congress and Mueller.

"I look forward with some confidence, having seen the people both in Congress and the special counsel's office, to them conducting a credible and thorough investigation, and I feel confident we'll have answers in due time," he said.