Sen. Barack Obama and Sen. Susan Collins hold double-digit leads over their opponents in the presidential and U.S. Senate races in Maine, according to a new poll released Wednesday by the U.S. Chamber of Commerce.

Obama, the presumptive Democratic presidential nominee, leads Sen. John McCain, the presumptive GOP nominee, by 12 points while Collins, a Republican, leads Democratic Rep. Tom Allen by 14 points.

In the presidential race, Obama leads McCain 49 to 37 percent and 11 percent are undecided. Collins leads Allen 55 to 41 percent.

Obama leads among voters under age 35, among women and he is running even with McCain among male voters.

McCain leads among older voters.

Obama leads 54 to 29 percent among independent voters, who outnumber registered Democrats and registered Republicans.

Obama and McCain are nearly tied among small business owners and self-described supporters of the business community.

The poll also sampled voters in the Portland media market and the Bangor – Presque Isle market. Obama led 50 to 36 percent in the southern part of the state and 49 to 38 percent in the northern part of the state.

See more below about the U.S. Senate race.

Democratic Rep. Tom Allen and Republican Sen. Susan Collins will face a third opponent in the Nov. 4 general election: Herbert Hoffman, an independent anti-war, pro-impeachment candidate.

Secretary of State Matt Dunlap on Monday rejected the Maine Democratic Party’s challenge to keep Hoffman off of the ballot. The party alleged that Hoffman’s petitions were invalid because he was not in the area where registered voters were signing them.

“I’m very gratified that the Secretary of State has upheld the hearing officer’s recommendation. This is a vindication of my petition efforts and it is also a ruling in favor of voters’ rights,” Hoffman said in a phone interview.

The ruling ends a two-week long dispute between Hoffman and the Maine Democratic Party, which began earlier this month when Hoffman submitted 4,112 signature to qualify for the ballot. He needed 4,000.

But the Maine Democratic Party challenged the validity of some of the signatures.

The two parties met at a hearing before the Secretary of State’s office on Monday. After reviewing the party’s complaints, Julie Flynn, Maine’s Deputy Secretary of State, found that 74 signatures were invalid, leaving Hoffman with 4,038 signatures.

“There’s no pattern of forethought of abuse,” Dunlap said, adding that the state party’s challenge “was not sufficient” to keep Hoffman off of the ballot.

Below is the statement from the Maine Democratic Party.

Sen. John McCain, the presumptive Republican presidential nominee, will attend a fundraiser at the home of former President George Bush in Kennebunkport on July 31, according to an invitation that has been sent out.

(UPDATE: The campaign says that this date is tentative and subject to change).

There is a photo-op with Bush and his wife, Barbara, at 11:30 and a small reception at 12 (that's for the high dollar donors). There's a bigger reception at The Colony Hotel on Ocean Avenue at 12:30.

Unless McCain or Sen. Barack Obama get to Maine before then, that will mark the first visit by a presidential candidate to the state. It's unclear now if McCain will hold a campaign rally.

Several senators and lobbyists feted Sen. Susan Collins, R-Maine, last week at the National Republican Senatorial Committee, helping her raise $50,000 in her bid for a third term.

Collins faces Rep. Tom Allen, D-Maine.

Republican Sens. Olympia Snowe of Maine, Arlen Spector of Pennsylvania, Thad Cochran of Mississippi and Orrin Hatch of Utah, attended the luncheon, according to Felicia Knight, Collins' deputy campaign manager.

The next quarterly reports must be filed by July 1 and they will be available to the public on July 15. We can then tell which lobbyists showed up and who gave how much.

Maine's Secretary of State's office denied a hearing on Friday to a third party candidate who failed to get the requisite number of signatures to qualify for a spot on the ballot in the fall.

Laurie Dobson of Kennebunk, who wanted to run for U.S. Senate as a pro-impeachment, anti-war candidate, failed to get 4,000 valid signatures. Without a hearing, she said she's going to court and plans to file a lawsuit in Maine Superior Court to argue that the state is not in compliance with the Help America Vote Act.

Meanwhile, Herbert Hoffman of Ogunquit, another independent candidate vying for a spot on the Senate ballot, will have his hearing on Monday before the Secretary of State's office to decide whether he has enough valid signatures to qualify for the ballot.

The Maine Democratic Party has contested Hoffman's petitions, alleging duplicative signatures, invalid addresses and a slew of other complaints.

Washington came to a screeching halt this afternoon upon learning that Tim Russert, 58, died of a heart attack. As everyone knows by now, Russert was the host of Meet the Press and NBC Washington Bureau Chief.

That's the lead story in today's issue of Roll Call, a trade publication that covers politics, lobbying, elections and all things Congress. It's subscription only so here's some of the text.

Here's what Sen. Chuck Schumer, D-N.Y., the chairman of the Democratic Senatorial Campaign Committee, had to say about Maine's Senate race:

Democrats believe they have a shot at winning as many as 11 GOP-controlled Senate seats this fall, with Schumer predicting the best shot at five — Virginia, New Hampshire, New Mexico, Colorado and Alaska, according to Roll Call.

Schumer cited Minnesota, Oregon and North Carolina as the next group of states for possible Democratic pickups, and three longer shots in the states of Mississippi, Maine and Kentucky, the latter of which is home to Senate Minority Leader Mitch McConnell.

“That’s just where the snapshot is now,” Schumer told Roll Call.

As Democrats try to unify the party after a bruising 17-month long primary campaign, conflict between two party leaders appears to linger from the 2006 campaign.

At a press conference on Tuesday, Speaker Nancy Pelosi of California praised Democratic National Committee Chairman Howard Dean's "50-state strategy," a plan to develop and build parties in all 50 states rather than just the traditional battleground states.

Dean pointed to his tie, which was designed with a red and blue map of the United States.

"Rahm told me to wear it today," Dean said.

If humor conceals one's true feelings, there might have been an element of a jab in Dean's comment.

In 2006, Dean and Rahm Emanuel, then chairman of the Democratic Congressional Campaign Committee, sparred over how and where to spend the party's money.

Dean wanted to spend to beef up state party organizations in so-called Republican-leaning "Red States" whereas Emanuel wanted to spend in states where Democrats were most likely to win House races.

Emanuel, frustrated that Dean was not committing more money to winning the House, cursed out Dean in a meeting in 2006. There's a Washington Post story about the meeting if you want to spend time Googling it.

Dean eventually pledged $250,000 for each competitive House race. Democrats won more than enough seats to reclaim the majority they lost in 1994.

The trade papers that cover Congress and elections here in Washington, D.C., have been writing on Maine's 1st Congressional District race in the lead up to today's primary.

Roll Call and Congressional Quarterly had articles in recent weeks (subscriptions are required). The Hill takes a stab today (full disclosure: that's where I worked before the Press Herald hired me).

The theme is all the same: as Chellie Pingree and Ethan Strimling run to the left, can first-time candidate Adam Cote win over enough moderate Democrats in the southern part of the district?

A non-profit group opposed to a key legislative priority for organized labor has confused Portland, Maine with Portland, Oregon.

"If Tom Allen thinks a private election is the best way to elect himself, why doesn’t he support the same system for working Oregonians?" the group writes on its Web site.

Of course, Democratic Rep. Allen is running in Maine against Sen. Susan Collins, a Republican, who is seeking a third term. Oregon features its own potentially competitive Senate race.

"Just as they don’t know much about hard-working Mainers, they seem to know even less about geography," Carol Andrews, Allen's spokeswoman, said.

Tim Miller, the group's spokesman, said it was a "typo."

A posting on the Employee Freedom Action Committee's website criticizes Allen for "doing labor's dirty work" by supporting the Employee Free Choice Act, a bill that the House approved last year to give employees the power to form a union through a process called "majority sign up." If a majority of employees sign a card approving a union, the employer must accept it. Current law requires a secret election.

Senate Republicans blocked a vote on the legislation by a 51-48 vote. Sens. Collins and Olympia Snowe, both Republicans, voted to continue debate on the measure.

Business groups are running television advertisements against the proposal and warning that if Democrats pick up enough seats in the November election, they will have a filibuster proof margin to pass the Employee Free Choice Act.

The New York Times had an interesting "Man in the News" profile of Sen. Barack Obama of Illinois on Wednesday, putting Obama "on the couch" to analyze the roots of his publicly cerebral and drama-free personality.

Here's an interesting nugget on how Obama reacted to winning Maine's Democratic caucuses on Feb. 10:

Told in February that he had won the caucuses in Maine, an overwhelmingly white state that he had expected to lose, he nodded, mumbled “That’s great,” and turned back to a phone call.

See the full story here.