After going on the attack with a controversial television ad, four-term incumbent U.S. Sen. Mitch McConnell (R-Louisville) continues to increase his polling lead over opponent Bruce Lunsford (D-Louisville), widening his lead to 12 points and hitting the 50-percent mark for the first time in this general election campaign, according to a new survey from Rasmussen Reports.

Meanwhile, the same firm shows presumptive Republican presidential nominee and U.S. Sen. John McCain (R-Ariz.) with a shrinking lead over his Democratic counterpart, U.S. Sen. Barack Obama (D-Ill.)

While a June survey from Rasmussen gave McConnell a 48 to 41 percent lead over Lunsford, the newest poll of 500 likely voters in Kentucky shows McConnell leading 50 to 38 percent. Ten percent of respondents in the new poll are undecided.

The margin of error in the new poll is plus or minus 4.5 percent. It was conducted on July 29, with both candidates already up on the air with television ads.

The timing of the poll incorporates the airing of McConnell's recent attack ad targeting Lunsford over gas prices as well as Lunsford's own response spot, which highlighted newspaper editorials deriding McConnell's ad as "dishonest."

Despite the attacks from either side, neither candidate's favorability ratings show any significant downticks.

Favorability numbers for the two show McConnell actually benefitting since last month's poll, with 55 percent of respondents rating the incumbent "very favorable" or "somewhat favorable." That number is down just one point since June.

Those rating McConnell as "very unfavorable" or "somewhat unfavorable" also dropped from 40 percent in June to 35 percent this month.

Lunsford's favorability figures stayed nearly the same, with a higher percentage of "unfavorable" ratings than "favorable." 45 percent of respondents rated Lunsford "very unfavorable" or "somewhat unfavorable" while 42 percent choose "very favorable" or "somewhat favorable" - numbers off just a point each from June.

McConnell gains support from 87 percent of Kentucky's Republicans and 26 percent of Democrats. Lunsford gets 67 percent of Democratic support and 9 percent of Republicans.

Among the "unaffiliated," 35 percent are undecided, 44 percent go to McConnell, and 16 percent to Lunsford.

Rasmussen also included numbers that account for so-called "leaners" that dilute the undecided population and show a slightly slimmer lead for McConnell, at 52 to 42 percent.

The 12-point lead in the Rasmussen numbers for McConnell is a stark turnaround from a May survey by the same firm that showed Lunsford up 5 points, 49 to 44 percent.

That pole was attacked by McConnell's camp and rebutted with the release of an internal poll, showing the incumbent up 50 to 39 percent.

Presidential race gets closer in the Commonwealth

McCain still holds a sizeable lead over Obama in Kentucky, but the race appears to be tightening up according to the new poll, which gives the Republican candidate a 49 to 39 percent lead.

That ten-point margin is a slight drop for McCain, who was up 51 to 35 in Rasmussen's June polling in Kentucky.

Seven percent of respondents in the new poll are undecided.

While there is some concern that Obama will not play well among Kentucky some Democrats, given his poor primary showing - a thirty-five point loss to U.S. Sen. Hillary Clinton (D-N.Y.) - the Illinois senator is gaining ground among his own party's supporters. According to the poll, 56 percent of Democrats now back Obama, up from 50 percent in June.

McCain still enjoys the support of a sizeable chunk of Democratic respondents, but the percent has fallen from 33 to 28 percent since the June survey. The Arizona senator also holds 79 percent support among Republicans.

Obama has made an eight point leap among independents since June while McCain's figures among the unaffiliated polled remains nearly the same after a month. McCain leads that group, 45 to 38 percent.

Despite these gains, favorability ratings show Obama still has his work cut out for him in the state. A full 50 percent of respondents rate Obama "very unfavorable" or "somewhat unfavorable" while McCain garners just 35 percent who rated him as such.

Obama received a rating of "very favorable" or "somewhat favorable" from 48 percent of respondents, compared to 60 percent for McCain.

In re-calibrated results accounting for "leaners," McCain enjoys a 52 to 43 percent lead over Obama.

Neither campaign has been particularly active in Kentucky thus far, though McCain's campaign named its state chair yesterday and Republican "victory" campaign offices are being organized at several locations across the state.

The new poll was conducted July 29 among 500 likely voters and has a margin of error of plus or minus 4.5 percent.

Update: The electorate's priorities

Rasmussen's presidential survey also included some barometers which give a sense for the political climate in Kentucky surrounding several particular issues.

Asked which issues "primarily interested" them "in terms of how you will vote for President," 42 percent of respondents indicated "economic issues" were the most important while 26 percent chose "national security issues." 12 percent indicated it was "domestic issues" that concerned them the most.

"Energy issues" was not an option, but Rasmussen also served respondents a question at the heart of the debate over potential expanded domestic oil exploration: "What is more important, reducing the price of gas and oil or protecting the environment?"

Sixty-three percent of respondents said reducing prices was more important, while 29 percent chose environmental protection.

Several questions also focused on the "war on terror." In two seperate inquiries, respondents were asked if a particular country was the "central front in the war on terror."

When asked that question about Iraq, 29 percent of respondents in Kentucky said "yes" while 52 percent said "no."

With regard to Afghanistan, 49 percent said it was "the central front" while 28 percent said it was not.

Fifty-two percent of respondents also said Afghanistan was a greater "threat" than Iraq. 28 percent indicated they held Iraq as a greater "threat" than Afghanistan.

Fifty-four percent of respondents indicated they thought the United States was "winning the War on Terrorism," while 24 percent gave that label to "terrorists" and 16 percent said neither group was winning.

Rasmussen also asked the 500 likely voters about their perception of the media's role in politics. A full 72 percent said they believed "most reporters" were "trying to help the candidate they want to win."

When asked which candidate "most reporters" would "try to help" in the presidential race this year, 58 percent selected Obama, 21 percent said their would be unbiased coverage and just 10 percent said McCain.