On Tuesday, August 3, Missouri will hold its U.S. Senate primaries. In November, the victors will face off to fill the seat of Christopher “Kit” Bond, a popular Republican senator who has been in office since 1986.

Despite some gruesome sideshows—including the write-in candidacy of mustachioed white supremacist Glenn Miller, whose radio spots must be heard to be believed—the result of Tuesday’s primaries is basically a foregone conclusion. A recent poll of regularly-voting Missourians, conducted by the St. Louis Post-Dispatch and local CBS affiliate KMOV-TV, had secretary of state Robin Carnahan leading her nearest Democratic challenger 87 percent to 5 percent (admittedly with a margin of error of 4 percentage points). In the crowded field for the Republican nomination, we’ve got more of a game on our hands—Representative Roy Blunt’s nearest challenger, Tea Party candidate and state senator Chuck Purgason, has at least managed to break double digits, with 13 percent to Blunt’s 62 percent. 19 percent of likely Republican primary voters remain undecided.

Carnahan and Blunt are both members of Missouri political dynasties. Robin Carnahan’s father, Mel, was governor of Missouri, and unseated incumbent John Ashcroft in the 2000 U.S. Senate race despite having died in a plane crash three weeks before the election. His widow, Jean, served out his term. Robin Carnahan’s brother Russ is a congressman. Roy Blunt’s son Matt served as Missouri secretary of state and then governor; Roy himself is a member of Congress who, as Republican whip, was thought a likely replacement for Tom DeLay as House Majority Leader. Both Blunt and Carnahan have nearly 100 percent name recognition in Missouri—and though voters have been known to confuse which Blunt and which Carnahan are actually on Tuesday’s ballot, the families’ legacies and policy positions are well-known in the state.

If introducing oneself to voters is a major purpose of campaigning in the first place, what will this race actually be about? Post-Dispatch political reporter and columnist Tony Messenger can sum it up in a word: Obama. Missouri bucked its long-cherished reputation as the bellwether state by narrowly choosing McCain in 2008—the President now has a 34 percent approval rating in the state. Proposition C, another August 3 ballot initiative aimed at allowing Missourians to opt out of the federal health insurance mandate, will be the first statewide referendum on the national health care overhaul signed into law in March. With no organized opposition, it looks likely to pass, though most legal experts have told local reporters that the law would have no effect, and is unconstitutional besides. (The Kansas City Star editorial board suggests the measure be rechristened “The Futile Gesture Act.”) Yet its backers hope it can send a message straight from the heartland to the White House.

Messenger has covered Missouri politics for over a decade for newspapers in Columbia and Springfield, and for the past two years for the St. Louis Post-Dispatch. Recently he told CJR three things he knows about this Senate race that you oughta. His thoughts, edited and condensed, appear below.

1. A Blunt/Carnahan matchup will serve as a conduit for national issues.

The fact that the Blunts and the Carnahans are both dynasties to some degree allows voters to focus on other issues. Neither candidate can really do anything to increase their name recognition. Carnahan is such a name that’s been around in Missouri politics for so long, longer than Blunt; within the Democratic Party it’s sort of a revered name but not necessarily with Republicans. Matt Blunt, the former governor, was not very popular at the end of his term, which hurts Roy Blunt a little bit, but the Blunts are still very popular with Republicans. To the extent that family associations damage either candidate, they sort of cancel each other out.

What I think this race is going to be about is President Obama. That’s what Roy Blunt is trying to make it about. And Robin Carnahan helped him a little bit by having Obama at a campaign rally in Kansas City earlier this month. Blunt was up with a TV ad within a week, using an image from that event with Obama saying, “If I had Robin Carnahan’s vote, we’d have cap-and-trade.” And cap-and-trade is very unpopular in Missouri because we’re a heavy coal plant state. So a big theme in the Blunt campaign is that we need to keep this Senate seat Republican, so that Democrats can’t just push through whatever they want.

Then the election really becomes a referendum on health care, on the stimulus and the bailout, on cap and trade, on all of those big-ticket items that have been on the national political landscape. Really, these two very well-known people have just become the conduits for those issues. Because everybody knows about as much as they’re going to know, if not about Robin Carnahan and Roy Blunt personally, [then about] their legacies—who these people are and what their families stand for.

So there’s an opportunity for this to be a race in which really the issues matter. Proposition C is a good example. Most of the legal experts I’ve talked to say it’s unconstitutional. But it’s similar to the Arizona immigration law in that the aim is to create a legal battle that will bring money into the Senate race, and will in turn give Blunt a way to talk about why Obama’s health care policy is bad. And Carnahan will have to respond.

Blunt came out with a clear statement in favor of Proposition C, and he wants to repeal the federal health care law. The Carnahan campaign issued a statement, where in long paragraph form they kind of said they’re against Prop C without ever saying they’re against Prop C. It’s an incredibly nuanced statement trying not to offend anybody, and it says very little at all. Whether he’s right or wrong, Blunt’s coming out with a pretty clear statement about something people have an opinion about. Carnahan has said some aspects of health care reform need to be changed—she is afraid to come out and say, “Yep, health care reform is a good law, and Blunt’s wrong.” It forces her into this position of nuance, and I’m not sure how well that plays politically.

2. The Tea Party has less influence in Missouri’s Republican Senate primary than it has in other Republican Senate primary races, but the outcome of Tuesday’s vote could determine the extent of their involvement in the national race come November.

Probably the most important thing about this race is that in no other state would a seven-term congressman named Roy Blunt, who’s very well known as a Washington insider, be the favorite. And yet he is. And it goes back to that political royalty thing. Blunt’s connections to Tom DeLay, Jack Abramoff, ethics questions, close ties to lobbyists—those things should hurt him. But many of them apply to Carnahan’s family as well.

Robin Carnahan herself is not an insider, but her brother’s in Congress, her mother was a senator, and her other brother has lobbied as well. All of the same things that she’s going to try to paint Roy with—it’s going to be like kindergarten: “I’m like rubber, you’re like glue.” A huge part of the Carnahan campaign has been “Blunt’s a Washington insider,” but it doesn’t seem to have the desired effect because her name is Carnahan. To some degree, they cancel each other out.

You look at what happened in Utah, Kentucky, and Florida—in all of those big races, the political insider lost to the Tea Party upstart. Here the Tea Party can’t get any support: Roy Blunt has all the cash. The Tea Party is for the most part backing a primary opponent to Roy Blunt, Chuck Purgason, but he’s not getting any national money, so without the money his grassroots support isn’t sufficient. And Michele Bachmann just threw her support behind Blunt. Her coming in angered a lot of the Tea Party folks in Missouri—Blunt voted for the bailout and is kind of the antithesis of what the Tea Party movement is about this year.

Robin Carnahan’s going to get like 80 percent of the Democratic vote on Tuesday. Blunt’s number’s not going to be as big because Purgason could take away some of his momentum; Purgason’s numbers on Tuesday could help determine whether the Tea Party is at all involved in the national election. If Blunt wins the primary, as is likely, and goes on to face Carnahan in November, those activists that are mad at Blunt and support his opponent are not likely to vote for Robin Carnahan—but the question is, do they vote in November? To me, Roy Blunt doesn’t bring in Michele Bachmann if he’s not at least a little bit worried about Tuesday. If this were the general election, he’s not bringing in Michele Bachmann, because she’s not going to help with independents.

3. Ultimately, the Senate race will be won or lost in southwest Missouri.

When people talk about a bellwether state, they sort of think that it’s a state that has a lot of independent voters. Missouri politically right now is not all that balanced. It’s fervently Republican in 85 percent of the state, and the urban areas are fervently Democratic. There’s no real purple in Missouri; it’s either red or blue, and it’s almost entirely red. The state legislature is completely controlled by the Republicans. Yet the governor, Jay Nixon, is a Democrat, as is Senator Claire McCaskill. Part of that is both of them were very effective at campaigning in some of the rural areas.

Nixon actually won Greene County, in southwest Missouri, where Roy Blunt’s from. Carnahan is probably going to run a similar campaign, getting out into those rural areas. She concentrates on letting people know she’s got a family farm in Rolla, in south central Missouri. She’s a lawyer, but she runs the farm as well. That is a similar strategy to what Nixon and McCaskill did. But the difference is that Roy Blunt is still incredibly popular in southwest Missouri. If you don’t get some numbers out of there you just can’t win in a general election. It’s going to be hard for Carnahan to get the sort of numbers McCaskill and Nixon got. Without those numbers, she will have to absolutely destroy him in the cities.

If you'd like to get email from CJR writers and editors, add your email address to our newsletter roll and we'll be in touch.

Kathy Gilsinan is the associate editor at World Politics Review