With conclusion of often-contentious debates for the August 3 gubernatorial primaries, emphasis in these closing days of the campaign will be on airways and grassroots -- TV ads and get-out-the-vote efforts.

Meanwhile, the endorsement ripples continue, with interest groups rallying their members for chosen candidates, and, in some cases, providing troops to knock on doors and make calls.

Some notable examples: the Michigan Chamber of Commerce and Michigan Right to Life are trumpeting efforts among their members for Republican Attorney General Mike Cox. Much of the membership of the Michigan AFL-CIO is doing the same for Democratic Lansing Mayor Virg Bernero big time.

How big? The Detroit Free Press said several unions could spend as much as $2.5 million to promote Bernero, who has been helped by a TV ad, paid by Flint area supporters, touting him and criticizing his primary opponent, House Speaker Andy Dillon of Redford.

Dillon’s TV ad touts him as a different kind of leader, and calls for more cooperation among elected officials.

In a significant development Friday, one powerful AFL-CIO affiliate, the 90,000-member Michigan Teamsters, which earlier endorsed Dillon in the Democratic primary, endorsed U.S. Representative Pete Hoekstra of Holland in the Republican primary.

"We've worked with Pete for many years and know that he is a leader that leads with the best interests of Michigan and its working families," Larry Brennan, president of Michigan Teamsters Joint Council 43, said of the congressman who earlier from Capitol Hill helped Teamsters root out corruption.

Hoekstra had one of the most effective TV ads in recent weeks -- a black and white one in which he sits in shirtsleeves and says in his nononsense way: "Yeah, government has a very big role in job creation: Get out of the way!" He squints just like gruff Clint Eastwood does in the superb Grand Torino movie (filmed in Metro Detroit) when he says to his neighbors, "Get off my lawn!"

Hoekstra then says: "Write this down: We are going to cut red tape and bureaucracy; we are going to cut spending."

One of the most effective ads by Cox, who attacked Hoekstra in an early ad, starts with his service as a Marine and concludes he would be one tough leader.

Oakland County Sheriff Mike Bouchard, like Hoekstra, has an ad in which he talks directly into the camera in shirtsleeves to tout his drive to make Michigan a Right to Work state. Bouchard, like Dillon, is a comfortable presence on the screen.

The former state legislator has a valued helpmate on the trail. Popular Secretary of State Terri Lynn Land, who is Bouchard's choice to run for lieutenant governor, campaigned recently Up North, including Manistee, Traverse City, Marquette, and Menominee.

Wealthy Ann Arbor venture capitalist Rick Snyder, who has dominated campaign ad airwaves since he introduced himself as one tough nerd in a Super Bowl TV ad that subsequently had a big buy in all Michigan markets, has done well (as has Dillon) on the endorsement front with diverse interests, including business and environmental groups.

Snyder was endorsed last week by Republicans for Environmental Protection, and likely this week will get the more broadly significant endorsement of the Michigan League of Conservation Voters.

Former state Senator and U.S. Representative Joe Schwarz of Battle Creek is to be announced this week to head an effort by Snyder to attract moderate Republicans, independents, and Democrats.

Senator Tom George, a Kalamazoo medical doctor, a well-qualified but under-funded contender who gets hardly a blip in polling for the GOP nomination, launched a modest radio-TV ad campaign last week. His pitch: "Michigan deserves a governor who will reform our state health programs, the single biggest expense within our budget, freeing up resources to afford tax relief and investments in education and roads. With our hard working people and bountiful natural resources, Michigan has a bright future. If we work together we can fix Michigan!"

The Stupak Seat

A leading Michigan political commentator who commissioned a poll on the Republican primary for the seat being vacated by nine-term Representative Bart Stupak says the result could be "A Tea Party scalp."

In this week's edition of Inside Michigan Politics (IMP) newsletter, editor/publisher Bill Ballenger said that robo-calls commissioned by IMP and conducted by East Lansing-based Practical Political Consulting (PPC) "says that Tea Party-supported Dan Benishek, a Crystal Falls physician, is the marginal leader" over term-limited state Sen. Jason Allen (R-Alanson).

Benishek received support from 20.7% of respondents; Allen got 19.3%.

Although the poll involved only 122 respondents willing to participate, IMP said the survey "reveals it's a two-man race - the other four candidates (including perennial candidate Don Hooper of Iron River) simply aren't clicking with Republican primary voters." Hooper was the 2004 and 2006 nominee against Stupak.

PPC co-partner Mark Grebner said, "It's clearly a race between Allen and Benishek, with no traction for anybody else. The undecided -- over 50% -- show there are still plenty of people left to persuade."

In an article posted online by MIRS news service, Ballenger said: "The conventional wisdom all along is that the Tea Party types will split up the vote against Allen, a major, towering establishment figure. This poll shows that isn't the case."

Allen campaign manager Jeremy Hendges, noting the small number of responses in the poll and the reaction Allen is getting while campaigning in the 31-county district, said Friday "we're not losing any sleep" over the poll.

Allen, who did not enter the race until Stupak said he would not seek reelection, out raised Benishek in the last quarter but trails Benishek, an early challenger of Stupak, slightly in contributions to date.

As reported last week by the Michigan Campaign Finance Network, Allen as of June 30 raised $221,968, $40,898 from political action committees. He had $177,249 cash on hand (a good sum for TV ads to start soon) and zero debt.

Benishek had raised $294,627, none from PACs. He had $280,659 cash on hand (some already spent on his TV ads) and a debt of $133,000 from what he loaned his campaign.

The Petoskey News-Review reports that Linda Goldthorpe, a Republican from McMillan, "reportedly has ended her active campaigning" for the primary. It said multiple calls to (the) Goldthorpe campaign for interviews went unanswered in the past two weeks."

It also said her backers have "moved on to support self-proclaimed GOP Tea Party candidate Tom Stillings from Torch Lake Township. Also running is Patrick Donlon” of St. Ignace Township.

State Representative Gary McDowell of Rudyard, who, like Allen, represents counties on both of Michigan's peninsulas, is the sole Democratic contender after several potential contenders declined.

McDowell as of June 30 raised $137,034, $77,500 from PACs. He had $136,136 on hand and a debt of $7,965. In the general election, he can count on substantial support from national party sources, including the various labor PACs that supported Stupak.

The IMP/PPC survey also looked at the southwest 6th District, where 12-term Representative Fred Upton (R-St. Joseph) "the most moderate Republican in the state's Congressional delegation, is being challenged by hardcore conservative ex-state Representative Jack Hoogendyk (R-Kalamazoo), it's no contest." Upton leads, 48.4% to 16.9%.

Hoogendyk got 34% of the vote as the 2008 Republican challenger of Senator Carl Levin.

George Weeks retired in 2006 after 22 years as political columnist for The Detroit News. His weekly Michigan Politics column is syndicated by Superior Features.