Here’s one measure of President Obama’s immense political talent, and of the force, compassion and eloquence with which he communicated his message of hope to a beleaguered nation in 2008: Obama’s coattails that year were enough to sweep even Mark Udall into the U.S. Senate.

Udall is running as an extremist on abortion, oddly obsessed with women’s sex lives and their menstrual cycle. Colorado’s voters are punishing him for it: Udall has fallen below 40 percent in the latest Quinnipiac poll and is probably among the three most endangered Senators this year.

Colorado has recently become a consistently, but only slightly, Democratic state. Since George W. Bush carried Colorado in 2004 with 51.7 percent (his fourth-narrowest win that year), Democrats have won every top-tier statewide race — Governor, U.S. Senator and President — for a decade. That’s seven for seven.

So if Udall loses by as much as the polls now suggest, it would say something about his candidacy. One message: Voters don’t like politicians who are obsessed with their sex lives.

Udall’s campaign website mentions “contraception” on 38 different pages, according to a Google search of the site. That’s more mentions than the “environment,” “immigration,” “climate” or “insurance.” “Contraception” shows up on more pages than “deficit” and “unemployment” combined. The phrase “war on women” shows up on more pages than does the new Middle Eastern threat of the Islamic State.

On top of that, Udall's campaign website mentions “birth control” on 71 different pages — that's more appearances than the word “America.”

Udall's first three ads of the general election were about birth control. “My opponent Congressman Gardner led a crusade that would make birth control illegal,” Udall said in one. His campaign’s YouTube page has 26 television ads, and 10 of them are about contraception.

“It really is 2014,” Udall says in one ad, “yet there are still politicians like Congressman Gardner supporting harsh anti-abortion laws and a bill to outlaw birth control.”

Of course, Gardner isn’t trying to outlaw birth control. As a limited-government conservative, Gardner actually supports allowing contraception sales over the counter, instead of requiring a prescription — an idea that makes Udall uneasy because it could endanger government subsidies.

Nontheless, Udall has persisted with his contraception obsession. An OB/GYN stars in one ad. His Spanish-language ad begins by promising Democrats “will always protect the rights of a woman to decide when she has children.”

In debates, when Udall has gotten questions about the economy, he has actually pivoted to contraception and abortion. Birth control is in his stump speech.

You can see how he earned the nickname "Mark Uterus."

Udall’s allies seem similarly obsessed with birth control. Udall loves talking about the environment, and so it makes sense that billionaire Democratic donor Tom Steyer — a staunch environmentalist — would pay for ads backing Udall. But Steyer’s latest ad is about birth control. The League of Conservation voters is also trying to help Udall with birth control ads.

NARAL, the abortion lobby's political action group, has run a TV ad and a radio ad threatening that a Gardner win would make condoms scarce. I’m not exaggerating.

According to an analysis by a local news station, more than half of the television spots run on his behalf — 53 percent — are on this topic.

Whence this obsession? It could be that Udall, his allies and his advisors spend too much time watching MSNBC and reading far-left websites — the provinces of media where those who oppose subsidizing contraception are accused of trying to ban it, and of wanting to “send condom police into America’s bedrooms,” in the words of one writer at Salon.

The Right has its birthers, and the Left has its birth-controllers — a tireless minority made up of conspiracy theorists who are immune to evidence. They get web traffic and even donations by inventing devious plots that the other side will supposedly implement once in power — FEMA camps for one side, condom cops for the other.

Obama got away with “war on women” talk in 2012. He put up proxies to misrepresent his contraception mandate and claim opponents were trying ban contraception. But Obama is Obama. Mark Udall is not.

Udall has rested his contraception campaign on two weak threads: Gardner’s opposition to Obama’s birth control mandate — which forces employers to provide insurance that includes contraception — and Gardner’s past support for legislation declaring that unborn babies are humans. Gardner stepped away from such “personhood” legislation when he realized it could affect the legality of some forms of contraception.

Had Udall tried to use birth control as a side issue, he might have had some success in fooling the press and some voters about what issues are at hand — just as Obama did. But once Udall decided to become Senator Uterus, he aborted himself.

If Udall loses, maybe Democrats will finally get the message that people don’t want politicians to obsess about imaginary conspiracies regarding their sex lives.