As Kentucky Secretary of State Alison Lundergan Grimes, a Democrat, strives to defeat Senate Minority Leader Mitch McConnell, a Republican, in the Bluegrass State, demographic factors show her challenge is growing steeper.

For the first time in six years, more Kentuckians identify as Republicans than Democrats. A new Gallup poll released Friday shows 45 percent of residents see themselves as part of the GOP while just 39 percent see themselves as aligned with Democrats. Just one year ago, 45 percent saw themselves as Democrats and 43 percent identified as Republicans.

The shift may be less about Grimes than the state’s distrust of President Barack Obama, who won just four out of 120 counties in the Bluegrass State during the 2012 presidential election. The Gallup survey found only 29 percent of people in Kentucky support the president – one more factor working against Grimes in her close midterm election.

The Kentucky Senate race was once billed as the most promising pick up opportunity for Democrats, a chance to unseat the Republican Party’s most powerful senator, a 30-year veteran. But over the last month, the national party's enthusiasm for Grimes appears to have leveled off. The Democratic Senatorial Campaign Committee is no longer running ads in the state on her behalf, a sign that the group is more invested elsewhere, perhaps in more winnable races like the contest in Georgia. And Grimes’s refusal to tell reporters who she voted for in the presidential election has become an awkward stumbling block on the campaign trail.

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Throughout her campaign, Grimes has tried to present herself as a new, fresh-faced opportunity for Kentucky. Her message has focused on solving economic inequality and bringing jobs back to Kentucky, which has lost 6,000 coal jobs since Obama took office in 2009. Local trust in the economy is faltering in the state as Kentuckians have one of the dimmest views of their economy in the nation. Yet, even with her energetic stump speeches and change-agent persona, Grimes may be working against a demographic sea change in Kentucky that would be tough for any candidate to overcome.

According to Gallup, when McConnell narrowly won re-election in 2008, the state was far more Democratic and national mood was hungry to rid itself of eight years of Republican control in the White House. Back then, 52 percent of Kentuckians identified as Democrats and only 38 percent said they were Republicans. Today, the electoral mood favors Republicans not just in Kentucky, but across the nation.