Oct. 27, 2008 -- Though a jury in Washington, D.C. has convicted Alaska Republican Sen. Ted Stevens on federal corruption charges, casting doubt on the future of his 40-year political career, the senator maintains his innocence and blames the verdict on "prosecutorial misconduct."

A federal grand jury indicted Stevens, 84, in July on seven counts of making false statements, for allegedly lying on U.S. Senate financial disclosure forms for the years 1999 to 2006.

The jury of eight women and four men deliberated for five hours Monday before returning guilty verdicts on all seven counts. Stevens held his hand to his stomach as the verdict was read in court.

Deliberations came to a halt late last week after a juror needed to leave town because of her father's death. The jury restarted its deliberations Monday with an alternate taking the place of that juror.

Prosecutors claimed that Stevens accepted $250,000 worth of gifts, primarily from now-defunct oil services company Veco Corp. and its former CEO, Bill Allen. Among the alleged gifts was the value of a home renovation project that transformed the senator's Girdwood, Alaska, home from a quaint cabin to a sizeable house, a $2,700 massage chair and a Viking gas grill.

The defense had said in court that the Stevens family paid more than $160,000 for the renovations, and Stevens testified that some of the gifts were instead loans, and others were left at his home by Allen. The defense contended that anything left off the disclosure forms was merely an oversight.

Stevens lashed out at prosecutors, releasing a statement saying he's "obviously disappointed in the verdict but not surprised given the repeated instances of prosecutorial misconduct in this case." The defense had filed mistrial requests, and the judge has said he's reviewing the actions of prosecutors after they sent a witness under subpoena home without telling the court and allegedly kept key evidence from the defense team.

"I will fight this unjust verdict with every ounce of energy I have," Stevens said. "I am innocent. This verdict is the result of the unconscionable manner in which the Justice Department lawyers conducted this trial. I ask that Alaskans and my Senate colleagues stand with me as I pursue my rights. I remain a candidate for the United States Senate."

Before boarding a plane in Virginia Monday afternoon, Alaska Governor and Republican vice-presidential nominee Sarah Palin commented on the verdict, calling it a "sad day" for Alaska, Stevens and his family, but added that "the verdict shines a light though on the corrupting influence of the big oil service company up there in Alaska that was allowed to control too much of our state."

Palin vowed a continued fight against corruption in her state, and said she's confident that Stevens "from this point on will do the right thing for the state of Alaska."

Each charge carries a maximum five years in prison and $250,000 fine. U.S. District Court Judge Emmet Sullivan will sentence Stevens in January.

Stevens, the longest-serving Republican senator, has been in office since 1968. During his four decades on Capitol Hill, he has become legendary for funneling millions in federal dollars to Alaska, including the "bridge to nowhere" project. Buildings and facilities all across Alaska, including the state's biggest airport, bear Stevens' name.

But the senator is also known for his orneriness. On days when he was spoiling for a fight in the Senate, Stevens often wore a tie bearing the angry comic book hero the Incredible Hulk. He even referred to himself as "a mean, miserable SOB."

Next week, he will face off with the Democratic challenger to his seat in the U.S. Senate, Anchorage mayor Mark Begich. Recent polls show a tight race, and Republican officials have admitted that the outcome of Stevens' trial will weigh heavily on the minds of Alaska voters and fellow senators who could vote to oust Stevens.

"If the trial comes to a conclusion and, as he believes, that he is found innocent, I think that he will win that election up there," National Republican Senatorial Committee chairman Sen. John Ensign, R-Nev. said last Tuesday. "If it goes the other way, obviously, it really won't matter what happens in the election."

Stevens is the latest Alaska Republican to fall amid the wide-ranging public corruption probe in that state. The investigation began in 2004, expanded to include Allen's company two years later and ensnared the senator after investigators became suspicious of Stevens' relationship with Allen.

Last year, federal agents searched Stevens' Girdwood home -- which he calls the "chalet" -- and Allen, the millionaire oilman, pleaded guilty to his own separate corruption charges. Seven other Alaskans, including the ex-speaker of the statehouse, a former vice president of Veco and a lobbyist, have been convicted as part of the probe.

Allen is the man on the other end of Stevens wiretaps, collected by the FBI. Prosecutors believed the recordings, which they played for the jury, proved that Stevens was aware he might be in legal trouble.

"They're not going to shoot us, it's not Iraq," Stevens can be heard saying on one tape. "We might have to pay a fine, might have to serve a little time in jail."

Stevens' attorneys are expected to appeal the conviction, but the senator's words could come back to haunt him soon enough.

ABC News' Imtiyaz Delawala and Luis Martinez contributed to this report.