Senate Democrats got exactly what they wanted in Missouri on Tuesday night. Now comes the hard part.

Republican Rep. Todd Akin’s primary victory clearly boosted vulnerable Democratic Sen. Claire McCaskill’s survival odds this fall. But to win, McCaskill will have to make the general election campaign as much about her opponent as herself.

That’s easier said than done. But Akin — and some of the things he’s said in the past — does make it a bit easier.

Republican U.S. Senate candidate Todd Akin celebrates his win in the senate primary race at his campaign party. (Christian Gooden/AP)

There’s a reason why Democrats spent over $1.5 million trying to help Akin win his three-way primary. He was the most conservative candidate in the field — and the most unpredictable one. He shook up his campaign staff late last year. He recently released a head-scratching and jumbled campaign ad. And Democrats have already launched a microsite highlighting his controversial statements that won’t play well with moderates. (“America has got the equivalent of the stage III cancer of socialism because the federal government is tampering in all kinds of stuff it has no business tampering in,” Akin once said.)

Akin is far from an ideal Republican nominee. But the GOP doesn’t need a superstar to defeat McCaskill. She is running in a state where Mitt Romney is expected to defeat President Obama. She will have to confront opposition ads that will attack her for billing taxpayers for trips she took on a plane she co-owned with her husband. She has long been one of the most high profile backers of the President.

And, recent polling from Mason Dixon Polling & Research Inc. shows McCaskill is losing to Akin by a slight margin. (It is worth noting that the same poll of the primary electorate showed businessman John Brunner leading Akin by 16 points.)

“I’m not going to tell you this is definitely a gimme for McCaskill, but I think the framework of the race is different,” said Democratic strategist Roy Temple, a veteran of Missouri politics.

In just about every Senate race featuring a vulnerable Democratic incumbent running in a state Obama is likely to lose, the GOP strategy has been consistent: Tie the Democrat to Obama and his policies via paid media efforts. Then, repeat.

In Missouri, the strength of this line of attack will be especially important for the GOP. Akin’s tendency to chart his own path (which, on occasion, has also been the politically problematic one) suggests that Democrats might be handed new fodder for their own attack ads this fall.

Akin’s uncompromising brand of social conservatism, for example, might lead him to say something that may give political moderates — the same moderates who don’t like the economic policies advanced by Obama and Senate Democrats — pause in the Senate race.

But to be clear, Akin isn’t even close to being on the same level of surprise 2010 primary winners like Sharron Angle (Nev.)and Christine O’Donnell (Del.) — two GOP Senate nominees with scant political resumes and even less political sense.

Akin has won congressional campaigns, he’s from the heavily populated St. Louis area and he doesn’t have any characteristics that blatantly disqualify him from serving in the Senate — particularly when running against a politically damaged incumbent like McCaskill and in a statewide political environment likely to be tipped toward Republicans.

“[McCaskill] can try to make the argument of, ‘Hey, this Republican is too conservative,’ but at the end of the day what’s more important to Missouri voters is they are worried about their financial future,” said Missouri Republican strategist James Harris, who worked for Sarah Steelman, one of Akin’s primary opponents.

Everything has to go right in the fall for McCaskill to survive. Akin has to slip up, she has to be flawless, and it may even take a little luck. But on this day, Democrats can argue that much of the race has gone right for them so far, with Akin’s win being the latest example of their strategy succeeding. And they’d be correct.