FRANKFORT, Ky. (AP) -- A new ad from an independent political group is giving voters a peek of the unrelenting barrage of negative ads linking likely Democratic Senate nominee Alison Lundergan Grimes with the as-unpopular-as-ever President Barack Obama.
"Obamacare. The war on coal. That's Obama's agenda. And Alison Grimes supports Obama," a female narrator says in the 30-second ad. "Now (Obama's) lieutenants are financing her campaign because Obama needs another vote in the Senate. And with Alison Grimes, that's what he'll get."
The ad -- which cost $552,000 -- began running on Friday and will continue through Kentucky's May 20 primaries. It is paid for by the Kentuckians for Strong Leadership, an independent political action committee run by Scott Jennings, a former adviser to President George W. Bush.
Of the $3.3 million the group has raised, just $172,000 has come from Kentucky addresses. Most of that -- $125,000 -- is from health insurance giant Humana founder David A. Jones Sr.
The Grimes campaign said its likely rival, Senate Republican Leader Mitch McConnell, has not done enough to protect coal country jobs.
"Alison Lundergan Grimes will oppose anyone who undermines our coal industry, and that includes the failed leadership of Mitch McConnell," Grimes spokeswoman Charly Norton said. "Alison is the only candidate in this race with a plan to protect coal jobs while diversifying our economy to attract new businesses that can create jobs here in the commonwealth."
The anti-Grimes ad comes as another independent group, the U.S. Chamber of Commerce, is airing a TV ad statewide in support of McConnell. The Chamber formally endorsed McConnell in March and pledged to spend more money on McConnell's race than in any other race in the country.
The out-of-state spending has helped McConnell build a sizeable and consistent advantage over his primary opponent Matt Bevin, a tea party favorite who has failed to catch fire.
Among likely Republican primary voters, McConnell leads with 57 percent of the vote, according to an NBC News/ Marist poll released Monday. Bevin wins support of just 25 percent of likely primary voters.
Bevin received a letter from the Federal Election Commission on Friday questioning him about a required report that may be incomplete or missing. The FEC gave Bevin's campaign until Thursday to complete a pre-primary financial report.
Bevin's most recent report, covering the campaign through March 31, listed him with $453,000 in the bank. The campaign also owes the candidate $600,000.
McConnell, meanwhile, reported more than $10 million in the bank, mostly for his expected race against Grimes in November.
Polling shows that race shaping up to be close.
The same NBC News/ Marist poll shows a race that's about even. McConnell is polling at 46 percent and Grimes is polling at 45 percent among registered voters. Keeping Kentucky in Republican hands is crucial to GOP efforts to pick up six Senate seats and capture the majority.
To help McConnell, outside groups are already turning toward Grimes.
For instance, the latest Kentuckians for Strong Leadership ad includes video of Grimes telling a man that she supports national Democrats' platform, which includes a goal of generating 80 percent of U.S. energy from clean energy sources by 2035. The Democratic National Committee platform includes an "all-of-the-above approach" to energy, including wind, solar, coal and natural gas.
But in coal-rich Kentucky, any threat to the mining industry or a perceived alliance with Obama are politically toxic charges and ones that Republicans and their allies will seize as November comes closer.
Obama lost Kentucky by double-digit margins in both of his presidential campaigns: 16 percentage points in 2008 and then by 23 points in 2012. And recent polling shows more than 60 percent of Kentuckians disapprove of the Democratic president. That's why McConnell and his allies are trying to get voters to think of Grimes as an Obama ally.
Grimes, meanwhile, has jumped at any chance to disagree with the president. She criticized his decision on new emission standards for coal-fired power plants. She criticized him for not approving the Keystone XL pipeline. And she criticized "the inexplicable decision of the Obama administration's Department of Education" to renew a contract with Sallie Mae to collect student loan payments.
The NBC News/ Marist survey of 2,353 registered voters was conducted by telephone with both landline and cellphones from April 30 to May 6. It has a margin of error of plus or minus 2 percentage points.
The same poll also surveyed 408 likely Republican primary voters and has a margin of error of plus or minus 4.9 percentage points within this group.
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