If the Republicans expect to staunch the Democratic trend in the Collar Counties, they must understand this: Bulldozers -- and, by extension, uncontrolled development -- is a dirty word.

Just a short generation ago, in the 1980s, the Republicans had an iron grip on the government machinery in DuPage, Kane, McHenry, Lake, Will and Kendall counties. Suburbanites had an us-versus-them mentality -- whatever Chicago wanted, they were against. And they had a phobia about taxes, which they wanted to be drastically lower. Less government was good government.

In 1984 Ronald Reagan carried the six counties by a combined 334,381 votes, while in 2004 George Bush won those counties by just 104,726 votes. The reason is not because the Republicans have grown too conservative on social issues; instead, it's because suburbanites have become markedly more affluent, and comprehend that it takes taxes to provide infrastructure, roads, schools, and police and other services.

In the last decade Democrats have surged in Collar County legislative and congressional races. In Lake County, directly north of Cook County, three state representatives and two state senators are Democrats. In McHenry County, northwest of Cook, one state representative and a U.S. representative are Democrats. And in Will County, south of Cook, four state representatives and two state senators are Democrats.

Will County, the site of the proposed Peotone Airport, which has been the site of invading hordes of political workers from Chicago, is on the way to becoming a pro-development Democratic bastion. In 2004 a Democrat was elected both state's attorney and county executive. But Lake County gives the Republicans cause for optimism: They have held most key county offices, county board spots and judgeships because they have astutely adopted a "moderate" position on development, while Democrats have let themselves become isolated as "greens," those seeking more open space and opposing most residential and commercial development.

The Republicans' wake-up call came in 1996, when Lake County Board chairman Bob Depke, who was known as "Bulldozer Bob," was defeated in the Republican primary. The county's population grew from roughly 104,000 in 1930 to 644,000 in 2000, and it is expected to eclipse 844,000 by 2030. Depke, of Gurnee, was a forthright, pro-development Republican. His philosophy was to build first and worry later about traffic congestion, flooding, land use and impact fees to build schools, roads, parks and libraries.

Depke's opposition came from open-space commissioners, who represented the county's already-developed eastern section of the county, generally east of Interstate 94, from Zion south to Highland Park and including Lake Forest and Lake Bluff, plus the southeast corner, including Deerfield, Lincolnshire and Vernon Hills. The pro-growth commissioners were from the less-developed western section, stretching from Lake Zurich to Antioch and including Wauconda, Lake Villa and Grayslake. Commissioners from the central section (Mundelein, Libertyville) tried to take a middle course. The suburbs that were already "grown" were most opposed to new growth.

Depke lost in 1996 to a "green" Republican, and Democrats won a few seats in the eastern section, but after the new board chairman, a Republican, embraced a balanced-growth agenda, the county's great "Bulldozer War" ended. The Republicans adapted to reality, and they have a solid majority on the 23-member board because they nominate commissioners who reflect their "green" or "bulldozer" constituencies.

In 2004 Lake County Republican State's Attorney Mike Waller was re-elected with 55 percent of the vote and Republican Circuit Court Clerk Sally Coffelt was re-elected with 57 percent. But two Democrats triumphed: Recorder Mary Ellen Vanderventer was re-elected with 58 percent of the vote, and Richard Keller beat incumbent Coroner Jim Wipper with 50.1 percent. Wipper, a funeral director, admitted using county vehicles to transport bodies to local crematoriums.

The county's Republican margin in presidential elections has dwindled. Reagan won by 64,454 votes in 1984, while Bush won by just 4,775 votes in 2004, which is only slightly less than his 2000 margin of 5,930. Rod Blagojevich lost the county in 2002 by 15,701 votes. The bottom line: Population growth in Lake County is in the west, where existing and incoming voters are generally conservative and Republican. That counteracts demographic change in the southeast, which is becoming more Democratic due to an influx of independent and Jewish voters. The Republicans' dominance will last for another decade.

McHenry County is now where Lake County was at in the early 1990s. Until recently McHenry was Illinois' fastest-growing county. Its population was just 35,000 in 1930, but it grew to 260,000 by 2000 and is expected to hit 500,000 by 2030. Growth and development are concentrated in the south and east, and the predominant political issue is traffic congestion. No interstate traverses the county, and rapid development has clogged the road system.

In the east, Route 31 runs northward from Algonquin through Lake in the Hills, Crystal Lake, Cary and McHenry and Route 47 runs northward from Huntley to Woodstock and Hebron, while in the west, Route 23 runs northward to Marengo and Harvard. The east-west conduits are Route 12, Route 14, Route 120 and Route 62. Local towns don't want to widen roads that pass through their downtown areas. As a result, traffic is perpetually snarled at all major intersections, not just during rush hour.

No Democrat has served on the 24-member McHenry County Board since before the Civil War, and Republicans hold every county office, but the party's margins are declining. In 1984 Reagan won the county by 32,862 votes, with 76.6 percent of the total in a turnout of 61,702, while 20 years later Bush won the county by 26,077 votes (60.2 percent) in a turnout of 126,665. Bush won the county in 2000 by 21,414 votes (60.4 percent) in a turnout of 102,810. The bottom-line: Unless the dominant Republicans make strides in solving the county's gridlock, Democrats and "greens" will soon become a factor in local politics.

DuPage County is the Republicans' bedrock. There are no Democratic state legislators or county office holders. The Republican margin in DuPage used to offset Democratic pluralities in Chicago and Cook County. No more.

In 1984 DuPage County delivered a 155,711-vote margin for Reagan (76 percent) in a turnout of 298,571; in 2004 it delivered a modest 34,832-vote margin for Bush (54.6 percent) in a turnout of 371,558. Hence, while the county vote has grown by more than 75,000 in 20 years, the Republican presidential vote has remained nearly steady, dropping from 227,141 in 1984 to 203,195 in 2004.

The Democratic presidential vote, by contract, has increased from 71,430 to 168,363 during that period. The reason is demographic change. DuPage County's population grew from 91,000 in 1930 to 904,000 in 2000, and it is expected to hit 1.1 million by 2030. Large numbers of Hispanics have settled in the county's northeast corner, in Bensenville, Addison and Itasca, and new upscale housing in the south, around Naperville, Lisle and Downers Grove, has brought in a flood of independent-minded, affluent residents.

The county government, which provides the jobs that produce the workers that power the Republican machine, still prospers. DuPage's Republican legislative contingent has brought in millions of state dollars for roadway improvements. Plenty of money is spent on schools and infrastructure. Bulldozers is not a dirty word, as population growth means economic growth, which means more tax dollars for more local projects. The Republicans are the "government party" in DuPage, and that won't change any time soon. Being anti-development is not a way for Democrats to succeed, but demographic change is helping them.

As for Will County, it may as well be declared a Republican disaster area. The Republicans' problem is demographics, not development. The county's population was 110,000 in 1930, but it exploded to 502,000 by 2000, and it will double to 1.1 million by 2030.

The principal reason is the migration of Chicago blacks to Cook County's south suburbs, which has pushed middle class whites southwestward, into Mokena, New Lennox and Frankfort. Their traditional Democratic inclinations, combined with the large Hispanic population in Joliet, Lockport and Romeoville, has made Will County a competitive area.

In 1984 Reagan won the county by 33,491 votes (63.5 percent) in a turnout of 123,877, while in 2004 Bush won the county by 13,489 votes (52.7 percent) in a turnout of 244,482. Peotone Airport is supposed to be built just east of Interstate 57 55, near Monee, and opposition in the county is minimal. Many view a new airport as an engine to create jobs and a vibrant local economy.

In 2004 the "Chicago connection" of State's Attorney Jeff Tomczak was politically fatal. His father, Don Tomczak, a former Chicago water department official, was charged with taking bribes in the federal "Hired Truck" investigation and pleaded guilty. Some of the bribe money allegedly ended up in his Republican son's campaign, as did many Chicago precinct workers. Tomczak beat Democratic incumbent Jim Glasgow in 2000, but the indictment of his father had an effect, and Glasgow won with 52 percent of the vote in 2004. In addition, Democrat Larry Walsh won the county executive post.

The bottom line: Will County will soon be a Democratic bastion.