As orators go, Gov. Harry Hughes is not the most electric. Delivering good news or bad, the governor is usually unemotional, dry and not the least bit flashy.

But give him the right material, such as the Reagan administration's latest tax plan, and Hughes the speechmaker becomes downright flamboyant.

At least he was last week in a scathing attack on the plan before an appreciative audience of Montgomery County Democrats, all of whom are aware that there is a U.S. Senate seat from Maryland open to challenge next year,

"Isn't he marvelous?" gushed one 74-year-old woman after Hughes gave what for him was an energetic speech to the Montgomery County Women's Suburban Democratic Club. "Do you think he wants to be in a Senate?"

Of course he does, say political handicappers around the state. Hughes himself is circumspect about challenging Sen. Charles McC. Mathias Jr., the respected liberal Republican whose term is up next year.

Asked at the club luncheon last week to describe his political plans, Hughes beamed and said, "No."

The crowd roared with delight, a testament to the many things the governor has going for him: Mathias' vulnerability on some issues, the roughly 3-to-1 edge that Democrats enjoy over Republicans in Maryland and Hughes' own credible record after seven years as governor.

That record, plus a public perception of Hughes as an able administrator, have made him a popular politician in places like Montgomery County. Voters like Hughes' style. They trust him. And some say they would vote for him over Mathias.

"He's a great governor," said one club member as she pulled a newspaper clipping from her purse. The story was a routine account of the hundreds of bills Hughes' had signed into law two months ago when the General Assembly adjourned.

"Just look at all these bills," the woman said: "Health care, childrens' programs. It's marvelous."

"He's competent, honest, has integrity and concern for the handicapped," said Shirley Lynn, 63, of Wheaton.

"He's been good at everything he's done," said Shirlee Marks of Bethesda. "He's honest and intelligent."

"And put in we think he can beat Mathias," piped up one of Marks' friends.

Some Democrats maintain that the breadth of support for Hughes is remarkable, showing up as it does 14 months before the Democratic primaries and on the heels of a savings and loan crisis that shook the Hughes administration -- not to mention thousands of account-holders -- to their boots.

But the jury is still out on what the eventual cost of the crisis will be to the state government, which has authorized $100 million to prop up shaky thrift institutions.

Equally unclear is whether the several state officials who knew how fragile the S&L system was long before it nearly collapsed will ever be held to account.

Such issues have yet to touch Hughes, but were certainly on his mind last week as he described for the 125 club members how his administration and the General Assembly reacted to the S&L crisis.

The speed with which the executive and legislative branches of government responded was "looked at with marvel around the country," Hughes said.

Well, maybe. Events virtually dictated the steps Hughes and the legislature had to take, although the state avoided the disaster Ohio suffered when all privately insured savings and loan associations were ordered closed.

Hughes's speech, which only touched on the still unresolved problems in the thrift industry, played very well in Rockville.

"It showed how much he's grown into the office," one listener said later. "This is the kind of guy we should have in the Senate."