With most of this year’s Senate primary elections complete, Democrats talk boldly about their chances in Kentucky and Mississippi, while Republicans gaze hungrily at Oregon and Colorado.

Time for a reality check.

Both parties face big hurdles in achieving such against-the-grain triumphs. Studies show it’s increasingly difficult for Senate candidates to win in states their party lost in the previous presidential election.

That leaves Republicans, virtually assured of keeping control of the House, hopeful about gaining the six seats they need this fall to control the Senate for President Barack Obama’s last two years in office.

Democrats are defending Senate seats in seven states that Obama lost, sometimes badly. All those races are leaning Republican or considered highly competitive.

The only Republican seeking re-election in an Obama-won state is Maine’s three-term Sen. Susan Collins, considered safe.

The GOP’s impressive recruiting has Republicans talking of possibly taking Democratic-held Senate seats in Oregon, Colorado, Iowa and other states Obama carried. Promising Democratic candidates in Kentucky and Georgia, plus bitter Republican infighting in Mississippi, have stoked talk of possible Democratic upsets in those states.

Anything is possible, of course. But those scenarios would defy recent trends in American voting.

“There’s a larger proportion of Senate seats going to the party that won the presidential election” in the state, said professor Gary Jacobson, who tracks such data at the University of California, San Diego. For all the talk of low approval ratings for Senate Republican leader Mitch McConnell in Kentucky, Jacobson said, “it’s a pretty red state. It’s tough to imagine him losing.”

Emory University political scientist Alan Abramowitz agreed. Senate races are becoming increasingly “nationalized,” he said. That means voters’ presidential sentiments are more likely to match their Senate choices.

The trend poses problems for Democrats in states such as Georgia and Kentucky, where Obama is largely unpopular, Abramowitz said.

On the flip side, the same trend erects serious barriers for Republicans trying to grab Senate seats in Oregon, Iowa, Colorado, Michigan and other states Obama carried. Republicans hope for an anti-Democratic wave, largely fueled by distaste for the president’s health law. Democrats say Republicans are choosing nominees too conservative for these states.

Not all Senate races adhere to the trend.

Four Democrats now seeking re-election proved that in 2008, by winning after their states voted Republican in the previous presidential contest: Mark Pryor of Arkansas, Mary Landrieu of Louisiana, Kay Hagan of North Carolina, and Mark Begich of Alaska. Hagan’s victory, however, came on the same day Obama narrowly carried her state. He lost North Carolina in 2012.

Privately, Democrats have all but conceded West Virginia and South Dakota, where Obama lost badly and longtime Democratic senators are retiring. They’re also deeply worried about Montana, where Obama also lost.

Few Senate races stir more passion than does Kentucky’s. Democrat Alison Lundergan Grimes, Kentucky’s secretary of state, is trying to oust McConnell. The five-term senator is poised to become majority leader if he survives and Republicans take over the Senate.

Strategists in both parties agree that if generic, plain-vanilla nominees were running, hardly anyone would consider Kentucky a serious Democratic prospect. But they note McConnell’s low approval ratings, and Grimes’ youthful, non-Washington image.

The same handicappers, however, often ignore the fact that some McConnell critics are fierce conservatives and extremely unlikely to vote for Grimes. McConnell, a ferocious and seasoned campaigner, will spend millions trying to persuade them to show their dislike for Obama by voting against the Democratic nominee, even if holding their noses.

“I have a very hard time seeing a scenario where he loses,” said GOP consultant Brian Walsh. “He’s got the best campaign team in the country,” he said, and Obama’s new limits on coal-fired power plants will hurt Grimes in the coal-producing state.

Georgia is a bit more worrisome for Republicans, Walsh said. Democratic political novice Michelle Nunn, daughter of former Sen. Sam Nunn, is running in a state where GOP Senate victories are almost routine. Two establishment-backed Republicans, businessman David Perdue and Rep. Jack Kingston, are competing for the GOP nomination.

Obama lost Georgia by only 7 percentage points in 2012 without seriously campaigning there, and Democrats say the state is trending their way. Privately, however, top strategists say a true Democratic tilt is probably several years away, and Nunn faces a tough battle.

Walsh said Republican campaign professionals feel confident about winning Senate seats in West Virginia, South Dakota and Montana. They would need only three more pick-ups to control the Senate.

(AP)